Polymerization Process And Reactor System

ABSTRACT

This invention is directed to processes for making polymer in the presence of a hydrofluorocarbon, and for the recovery of polymer substantially free of dissolved hydrocarbons and hydrofluorocarbons. The processes provided enables polymerization processes to be practiced with minimal fouling in the reaction system, and with the recovery of the hydrofluorocarbon and monomers for reuse in the reactor. The process of the invention utilizes a reactor system, a recovery system and a flare system that minimize environmental emissions of hydrocarbons, hydrofluorocarbons and associated decomposition products.

FIELD OF THE INVENTION

This invention relates to a polymerization process and a reactor systemfor making a polymer product. In particular, this invention relates to apolymerization process using a hydrofluorocarbon, and a reactor systemproviding for the recovery of the polymer product and thehydrofluorocarbon.

BACKGROUND OF THE INVENTION

Polymerization generally involves polymerization of one or more monomersto make a polymeric product. The polymerization reaction can be carriedout using a wide variety of reactors, catalysts, and a wide variety ofmonomer feeds. Often, liquids, diluents or solvents are used in thesepolymerization reaction processess for various reasons such as toincrease the efficiency of the polymerization reaction and recovery ofpolymer product.

An example of a polymerization process that incorporates the use of adilutent is shown in U.S. Pat. No. 3,470,143 (Schrage et al.).Specifically, the Schrage patent discloses a laboratory scalepolymerization reaction that incorporates the use of an organicfluorinated carbon compound as the dilutent.

Polymer production at commercial scale typically results in theproduction of a polymer product having significant amounts of entrainedhydrocarbon material such as unreacted monomer, as well as variouslevels of liquids, solvents, diluents, catalysts and other by-productsand/or non-reactive components. Separation and recovery of the polymerproduct from such a mixture of components typically involves passing thepolymer product withdrawn from the polymerization reactor into purgebins, with nitrogen typically introduced into the purge bin to removethe undesirable materials from the polymer product. Conventionally, thenitrogen and undersirable material are vented or sent to a flare systemas a waste stream.

U.S. Pat. No. 5,769,927 (Gottschlich et al.) discloses a process fortreating material that is to be vented or purged from a polymermanufacturing operation using a three step separation technique. Thetechnique includes condensation, flash evaporation and membraneseparation to remove components such as ethylene, propylene andnitrogen.

U.S. Pat. No. 6,271,919 (Baker et al.) discloses a polypropylenemanufacturing process that includes using a gas separation membrane toseparate propylene from propane in a reactor vent stream. The separatedpropylene is circulated back to the polymerization reactor as feed.

EP 1 323 746 shows loading of biscyclopentadienyl catalyst onto a silicasupport in perfluorooctane and thereafter the prepolymerization ofethylene at room temperature.

U.S. Pat. No. 3,056,771 discloses polymerization of ethylene usingTiCl₄/(Et)₃Al in a mixture of heptane and perfluoromethylcyclohexane,presumably at room temperature.

There are needs for improved polymerization processes, for examplereducing reactor fouling at commercial scale, enhancing the commercialgrade slate of polymer products produced from a given process,increasing polymer production capacity without significant investmentwhere these process improvements necessitate more efficient recoverysystems that provide environmental benefits as well as cost reductions.Therefore, depending on the various components used in polymerizationprocesses improvements, polymer product recovery and reactor systems forrecovering reusable materials and lowering emissions is needed,particularly in light of ever changing environmental constraints thatcontinue to be imposed in the chemical manufacturing industry.

SUMMARY OF THE INVENTION

The invention provides a process for making a polymer product and apolymer reactor system where a hydrofluorocarbon is used in the process.The invention further provides for a reactor system for use with ahydrofluorocarbon, and for recovery of the hydrofluorocarbon and otherhydrocarbons or compounds that are typically reusable in apolymerization process. Also, this invention provides for any type ofpolymerization process and polymer product recovery and hydrocarbonrecovery processes that couple together the benefits of reduced reactorfouling and efficient polymer product recovery with low emissions.

According to one aspect of the invention, there is provided a processfor polymerizing one or more monomer(s) in a reactor system, the reactorsystem comprising a reactor and a flare system, the process comprisingthe steps of: a) introducing a catalyst system and the one or morehydrocarbon monomers, in the presence of a hydrofluorocarbon, to thereactor, producing polymer and hydrocarbon by-products; b) recovering atleast a portion of the hydrocarbon by-products from thehydrofluorocarbon and polymer as a waste stream; and c) sending at leasta portion of the waste stream to the flare system. In yet anotherembodiment, the invention is directed to a process for polymerizing oneor more monomer(s) in a reactor system, the reactor system comprising areactor and a flare system, the process comprising the steps of: a)introducing a catalyst system and the one or more monomers, in thepresence of a hydrofluorocarbon, to the reactor producing a polymerproduct and by-products, the by-products comprising a portion of thehydrofluorocarbon; b) removing a portion of the hydrofluorocarbon fromthe by-products prior to the remaining by-products entering the flaresystem. In another embodiment, the by-products further comprise nitrogenand one or more of the monomer(s), wherein in addition to removal of aportion of the hydrofluorocarbon, portions of the nitrogen and/or one ormore monomer(s) are removed prior to the remaining by-products enteringthe flare system.

According to another aspect of the invention, there is provided aprocess for polymerizing one or more monomer(s) in a reactor system, thereactor system comprising a reactor and a flare system. The processcomprises mixing together a catalyst system, the one or more monomersand a hydrofluorocarbon in the reactor to produce polymer. There isrecovered from the mixture a plurality of streams, including ahydrofluorocarbon containing stream, a polymer product stream and awaste stream. At least a portion of the waste stream is sent to theflare system.

In another embodiment if the invention, there is provided apolymerization process that comprises forming a polymer in the presenceof a hydrofluorocarbon. A majority of the polymer is recovered in apolymer product stream and a majority of the hydrofluorocarbon in apurge stream. The purge stream is separated into a plurality of streamsincluding a hydrofluorocarbon containing stream and a waste stream. Atleast a portion of the waste stream is sent to a flare stream.

In another embodiment, the process of the invention comprises separatinghydrofluorocarbon from a polymer and recovering the separatedhydrofluorocarbon in a purge stream. The purge stream is separated intoa plurality of streams including a hydrofluorocarbon containing streamand a waste stream, and at least a portion of the waste stream is sentto a flare system.

In yet another embodiment, there is provided a polymerization process inwhich at least one monomer is polymerized to form polymer in a mixturecontaining hydrofluorocarbon. A plurality of streams, including a wastestream, is recovered from the mixture, and at least a portion of thewaste stream is sent to a flare system.

In one embodiment, the waste stream is sent to the flare system at ahydrofluorocarbon flow rate to unit production flow rate of not greaterthan 0.1:1. Preferably, the waste stream is sent to the flare system ata hydrofluorocarbon flow rate to unit production flow rate of notgreater than 0.01:1, more preferably not greater than 0.001:1.

In another embodiment, the mixture is purged with a nitrogen stream andthen the plurality of streams is recovered. Preferably, the plurality ofrecovered streams includes a nitrogen containing stream. Morepreferably, the nitrogen containing stream contains a majority of thenitrogen used to purge the polymer product.

In one embodiment, the waste stream is sent to the flare system at anitrogen flow rate that is not greater than 6% of unit production rate.Preferably, the waste stream is sent to the flare system at a nitrogenflow rate that is not greater than 3%, more preferably not greater than1%, and most preferably not greater than 0.5% unit production rate.

A plurality of streams can be recovered from the product mixture throughone or more separation systems. Examples of such systems include, butare not limited to compression, flashing, cooling, condensation,distillation, selective barrier separation or a combination thereof.Preferably, the plurality of streams is recovered through condensationand selective barrier separation.

The polymerization process can be carried out in any variety of modes.For example, the polymerization process can be carried out as a solutionprocess, gas phase process, slurry phase process, medium pressureprocess, high pressure process or a combination thereof.

The recovered polymer product stream is typically low in contaminants.In one embodiment, the recovered polymer product stream contains notgreater than 100 wppm total hydrofluorocarbon, based on total weight ofthe recovered polymer product stream.

BRIEF DESCRIPTION OF THE DRAWINGS

The attached Figures represent various aspects of the invention. TheFigures are intended to be viewed as merely examples of specificembodiments within the scope of the overall invention as claimed.

FIG. 1 a is a generic flow diagram of the polymer recovery system ofthis invention.

FIG. 1 b is a generic flow diagram of the polymer recovery system ofthis invention that includes a flash tank.

FIG. 2 a is a flow diagram of one embodiment of the invention that usesa first and second separation to first recover a hydrocarbon rich streamand then a nitrogen rich stream.

FIG. 2 b is a flow diagram of one embodiment of the invention that usesa first and second separation to first recover a nitrogen rich streamand then a hydrocarbon rich stream.

FIG. 3 is a flow diagram of one embodiment of the invention thatincludes a condensation system and a barrier separation system.

DETAILED DESCRIPTION OF THE INVENTION

I. Introduction

This invention is directed to a process for polymerizing one or moremonomer(s) in the presence of a catalyst system and a hydrofluorocarbonin a reactor, and in combination with a separation system for removingvarious compounds from the process. The separation system is designed inone embodiment for preventing substantially all or all of thehydrofluorocarbon from being vented to the atmosphere or flared in theflare system. One issue concerning venting or flaring of thehydrofluorocarbons is that the hydrofluorocarbon can form acidmaterials, for example, hydrogen fluoride (HF). These acid materialsresult in corrosion or environmental contamination. Therefore, while theinvention relates to a polymerization process using hydrofluorocarbons,without the recognition for avoiding venting or flaring of thehydrofluorocarbon, the benefits of the process of the invention wouldnot be commercially viable.

II. Making and Recovering Polymer

This invention is directed to processes for making polymer andrecovering a polymer product with minimal fouling, thus resulting inimproved operation efficiency, with low loss of heat transfer andextended run periods. Also, the invention provides for the production ofpolymers not typically capable of being produced in a given processthereby expanding the commercial grade slate from a particular process.

In addition to the production and recovery of polymer from the process,the invention provides for higher recovery of hydrocarbons that arerecovered along with the polymer. Such hydrocarbons includenon-polymerized materials, for example liquids, diluents, solvents, andunreacted monomers. Many of these non-polymerized materials arerecovered at high efficiency and reused in the polymerization process.Additionally, the recovery process further provides the benefit ofreducing potential corrosion and other environmental problems relatingto the venting or flaring of hydrocarbon waste streams; a waste streambeing any stream that contains components removed from the reactionprocess and not reused in that process. Such waste streams includesthose streams that are removed from the reaction process by venting intothe atmosphere or flaring.

One general embodiment of the invention is accomplished by forming apolymer in the presence of diluent material effective in reducingreactor fouling, such as hydrofluorocarbon (HFC). The HFC diluent isseparated from the polymer along with hydrocarbon by-products from thereaction process, and at least a portion of the undesirable hydrocarbonby-products is removed from the reaction system as a waste stream.

A particularly effective manner of removing or venting the purge streamis to flare or burn the waste stream. Preferably, the waste stream islow in diluent and non-combustible material to reduce environmentalcontamination. The compounds in the waste stream that are vented have alower flow rate relative to the unit production flow rate compared tothat of conventional processes. This lower flow rate means that lessenvironmentally contaminating materials will leave the reaction system,and that a greater amount of materials can be recovered and reused inthe polymerization process.

III. Monomers

The processes described herein may be used in any type of polymerizationprocess employing one or more monomers. Typical monomers includeunsaturated hydrocarbons having from 2 to 30 carbon atoms, preferably 2to 12 carbon atoms, and more preferably 2 to 8 carbon atoms. Usefulmonomers include linear, branched or cyclic olefins; linear branched orcyclic alpha olefins; linear, branched or cyclic diolefins; linearbranched or cyclic alpha-omega olefins; linear, branched or cyclicpolyenes; linear branched or cyclic alpha olefins. Particularlypreferred monomers include one or more of ethylene, propylene, butene-1,pentene-1,4-methyl-pentene-1, hexene-1, octene-1,decene-1,3-methyl-pentene-1, norbornene, norbornadiene,3,5,5-trimethyl-1-hexene, 5-ethyl-1-nonene, vinyl norbornene, ethylidenenorbornene monomers.

Preferred cyclic containing monomers include aromatic-group-containingmonomers containing up to 30 carbon atoms and non aromatic cyclic groupcontaining monomers containing up to 30 carbon atoms. Suitablearomatic-group-containing monomers comprise at least one aromaticstructure, preferably from one to three, more preferably a phenyl,indenyl, fluorenyl, or naphthyl moiety.

The aromatic group-containing monomer further comprises at least onepolymerizable double bond such that after polymerization, the aromaticstructure will be pendant from the polymer backbone. The aromatic-groupcontaining monomer may further be substituted with one or morehydrocarbyl groups including but not limited to C₁ to C₁₀ alkyl groups.Additionally two adjacent substitutions may be joined to form a ringstructure. Preferred aromatic-group-containing monomers contain at leastone aromatic structure appended to a polymerizable olefinic moiety.Particularly preferred aromatic monomers include styrene,alpha-methylstyrene, para-alkylstyrenes, vinyltoluenes,vinylnaphthalene, allyl benzene, and indene, especially styrene,paramethyl styrene, 4-phenyl-1-butene and allyl benzene. Suitablenon-aromatic cyclic group containing monomers preferably have at leastone polymerizable olefinic group that is either pendant on the cyclicstructure or is part of the cyclic structure. The cyclic structure mayalso be further substituted by one or more hydrocarbyl groups such as,but not limited to, C₁ to C₁₀ alkyl groups. Preferred non-aromaticcyclic group containing monomers include vinylcyclohexane,vinylcyclohexene, vinylnorbornene, ethylidene norbornene,cyclopentadiene, cyclopentene, cyclohexene, cyclobutene, vinyladamantaneand the like.

Preferred diolefin monomers useful in this invention include anyhydrocarbon structure, preferably C₄ to C₃₀, having at least twounsaturated bonds, wherein at least two of the unsaturated bonds arereadily incorporated into a polymer by either a stereospecific or anon-stereospecific catalyst(s). It is further preferred that thediolefin monomers be selected from alpha, omega-diene monomers (i.e.di-vinyl monomers). More preferably, the diolefin monomers are lineardi-vinyl monomers, most preferably those containing from 4 to 30 carbonatoms. Examples of preferred dienes include butadiene, pentadiene,hexadiene, heptadiene, octadiene, nonadiene, decadiene, undecadiene,dodecadiene, tridecadiene, tetradecadiene, pentadecadiene,hexadecadiene, heptadecadiene, octadecadiene, nonadecadiene, icosadiene,heneicosadiene, docosadiene, tricosadiene, tetracosadiene,pentacosadiene, hexacosadiene, heptacosadiene, octacosadiene,nonacosadiene, triacontadiene, particularly preferred dienes include1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene,1,10-undecadiene, 1,11-dodecadiene, 1,12-tridecadiene,1,13-tetradecadiene, and low molecular weight polybutadienes (Mw lessthan 1000 g/mol). Preferred cyclic dienes include cyclopentadiene,vinylnorbornene, norbornadiene, ethylidene norbornene, divinylbenzene,dicyclopentadiene or higher ring containing diolefins with or withoutsubstituents at various ring positions.

In a preferred embodiment the polymer produced herein is an ethylenehomopolymer or copolymer. In a particularly preferred embodiment, theprocess of this invention relates to the polymerization of ethylene andone or more C₄ to C₂₀ linear, branched or cyclic monomers, preferably C₄to C₁₂ linear or branched alpha-olefins. In a preferred embodiment, thecomonomer comprises at least one comonomer having from 3 to 8 carbonatoms, preferably 4 to 8 carbon atoms. Particularly, the comonomers arepropylene, butene-1,4-methyl-pentene-1,3-methyl-pentene-1, hexene-1 andoctene-1, the most preferred being hexene-1, butene-1 and or octene-1.

In a preferred embodiment the polymer produced herein is a propylenehomopolymer or copolymer. In a particularly preferred embodiment, theprocess of the invention relates to the polymerization of propylene andone or more C₄ to C₂₀ linear, branched or cyclic monomers, preferably C₄to C₁₂ linear or branched alpha-olefins. In a preferred embodiment, thecomonomer comprises at least one comonomer having from 2 to 8 carbonatoms, preferably 4 to 8 carbon atoms, preferably ethylene, butene-1,pentene, hexene-1, heptene-1, octene-1, nonene-1, decene-1,dodecene-1,4-methyl-pentene-1,3-methylpentene-1,3,5,5-trimethyl-hexene-1, and the like. In some embodiments,ethylene is present at 5 mol % or less.

In another embodiment the polymer produced herein is a copolymer of oneor more linear or branched C₃ to C₃₀ prochiral alpha-olefins or C₅ toC₃₀ ring containing olefins or combinations thereof capable of beingpolymerized by either stereospecific and non-stereospecific catalysts.Prochiral, as used herein, refers to monomers that favor the formationof isotactic or syndiotactic polymer when polymerized usingstereospecific catalyst(s).

In another embodiment ethylene or propylene is polymerized with at leasttwo different comonomers to form a terpolymer. The preferred comonomersare a combination of alpha-olefin monomers having 4 to 10 carbon atoms,more preferably 4 to 8 carbon atoms, optionally with at least one dienemonomer. The preferred terpolymers include the combinations such asethylene/butene-1/hexene-1, ethylene/propylene/butene-1,propylene/ethylene/hexene-1, ethylene/propylene/norbornene and the like.

In a preferred embodiment, the monomer is present in the polymer at 50mole % to 99.9 mole %, more preferably 70 to 98 mole %, and morepreferably 80 to 95 mole %. Comonomer(s) are present in the polymer at0.1 mole % to 50 mole %, based upon the moles of all monomers present,more preferably 2 to 30 mole %, more preferably 5 to 20 mole %.

In another embodiment, the polymer produced herein comprises:

a first olefin monomer present at from 40 to 100 mole %, preferably 50to 100 mole %, more preferably 60 to 100 mole %, and

a second olefin monomer (a comonomer) present at from 0 to 60 mole %,preferably 0 to 30 mole %, more preferably 0 to 10 mole %, andoptionally

a third olefin monomer present at from 0 to 10 mole %, more preferablyfrom 0 to 5 mole %, more preferably 0 to 3 mole %.

In a preferred embodiment the first olefin monomer comprises one or moreof any C₃ to C₈ linear, branched or cyclic alpha-olefins, includingpropylene, 1-butene, (and all isomers thereof), 1-pentene (and allisomers thereof), 1-hexene (and all isomers thereof), 1-heptene (and allisomers thereof), and 1-octene (and all isomers thereof). Preferredmonomers include propylene, 1-butene, 1-hexene, 1-octene, and the like.

In a preferred embodiment the second olefin monomer comprises one ormore of any C₂ to C₄₀ linear, branched or cyclic alpha-olefins,including ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene,and 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-hexadecene,butadiene, hexadiene, heptadiene, pentadiene, octadiene, nonadiene,decadiene, dodecadiene, styrene,3,5,5-trimethylhexene-1,3-methylpentene-1,4-methylpentene-1,cyclopentadiene, and cyclohexene.

In a preferred embodiment the third olefin monomer comprises one or moreof any C₂ to C₄₀ linear, branched or cyclic alpha-olefins, includingbutadiene, hexadiene, heptadiene, pentadiene, octadiene, nonadiene,decadiene, dodecadiene, styrene,3,5,5-trimethylhexene-1,3-methylpentene-1,4-methylpentene-1,cyclopentadiene, and cyclohexene.

IV. Liquid, Diluent, Solvent, Solution

The diluents used in this invention are beneficial in producing highlyuseful polymer products. Use of the diluents can also provide polymerprocesses having reduced fouling, higher overall efficiencies and/orreduced environmental emissions. The diluents of the invention arepreferably compositions added to the reaction process that reduce theconcentration of one or more active materials in the process to achievethe desired and beneficial effect. Preferably, the diluent is ahydrocarbon having little to no solvent power. More preferably, thediluent is a halogen containing compound, most preferably a fluorinatedhydrocarbon compound, and preferably a compound having little to nosolvent power with respect to the polymer product. The fluorinatedhydrocarbons may be used individually or as mixtures, and can beincluded in a mixture with non-fluorinated hydrocarbon diluents ifdesired.

According to this invention, fluorinated hydrocarbons are compoundshaving at least one carbon atom and at least one fluorine atom. Thefluorinated hydrocarbon can be a perfluorinated hydrocarbon or thefluorinated hydrocarbon can optionally include one or more hydrogenatom(s). A perfluorinated hydrocarbon is a fluorocarbon in which thehydrogen directly attached to the carbon atom(s) is completely replacedby fluorine. See Hawley's Condensed Chemical Dictionary, ThirteenthEdition, Van Nostrand Renhold, 1997. Examples of preferredperfluorocarbons include linear branched or cyclic, C₁ to C₄₀,preferably C₁ to C₂₀, more preferably C₁ to C₁₀, and most preferably C₁to C₆ perfluoroalkanes.

In one embodiment, the fluorinated hydrocarbons are represented by theformula:C_(x)H_(y)F_(z)  (XII)wherein x is an integer from 1 to 40, alternatively from 1 to 30,alternatively from 1 to 20, alternatively from 1 to 10, alternativelyfrom 1 to 6, alternatively from 2 to 20 alternatively from 3 to 10,alternatively from 3 to 6, most preferably from 1 to 3, wherein y isgreater than or equal to 0 and z is an integer and at least one, morepreferably, y and z are integers and at least one. In a preferredembodiment z is 2 or more.

Examples of hydrofluorocarbons include fluoromethane; difluoromethane;trifluoromethane; fluoroethane; 1,1-difluoroethane; 1,2-difluoroethane;1,1,1-trifluoroethane; 1,1,2-trifluoroethane; 1,1,1,2-tetrafluoroethane;1,1,2,2-tetrafluoroethane; 1,1,1,2,2-pentafluoroethane; 1-fluoropropane;2-fluoropropane; 1,1-difluoropropane; 1,2-difluoropropane;1,3-difluoropropane; 2,2-difluoropropane; 1,1,1-trifluoropropane;1,1,2-trifluoropropane; 1,1,3-trifluoropropane; 1,2,2-trifluoropropane;1,2,3-trifluoropropane; 1,1,1,2-tetrafluoropropane;1,1,1,3-tetrafluoropropane; 1,1,2,2-tetrafluoropropane;1,1,2,3-tetrafluoropropane; 1,1,3,3-tetrafluoropropane;1,2,2,3-tetrafluoropropane; 1,1,1,2,2-pentafluoropropane;1,1,1,2,3-pentafluoropropane; 1,1,1,3,3-pentafluoropropane;1,1,2,2,3-pentafluoropropane; 1,1,2,3,3-pentafluoropropane;1,1,1,2,2,3-hexafluoropropane; 1,1,1,2,3,3-hexafluoropropane;1,1,1,3,3,3-hexafluoropropane; 1,1,1,2,2,3,3-heptafluoropropane;1,1,1,2,3,3,3-heptafluoropropane; 1-fluorobutane; 2-fluorobutane;,1-difluorobutane; 1,2-difluorobutane; 1,3-difluorobutane;1,4-difluorobutane; 2,2-difluorobutane; 2,3-difluorobutane;1,1,1-trifluorobutane; 1,1,2-trifluorobutane; 1,1,3-trifluorobutane;1,1,4-trifluorobutane; 1,2,2-trifluorobutane; 1,2,3-trifluorobutane;1,3,3-trifluorobutane; 2,2,3-trifluorobutane; 1,1,1,2-tetrafluorobutane;1,1,1,3-tetrafluorobutane; 1,1,1,4-tetrafluorobutane;1,1,2,2-tetrafluorobutane; 1,1,2,3-tetrafluorobutane;1,1,2,4-tetrafluorobutane; 1,1,3,3-tetrafluorobutane;1,1,3,4-tetrafluorobutane; 1,1,4,4-tetrafluorobutane;1,2,2,3-tetrafluorobutane; 1,2,2,4-tetrafluorobutane;1,2,3,3-tetrafluorobutane; 1,2,3,4-tetrafluorobutane;2,2,3,3-tetrafluorobutane; 1,1,1,2,2-pentafluorobutane;1,1,1,2,3-pentafluorobutane; 1,1,1,2,4-pentafluorobutane;1,1,1,3,3-pentafluorobutane; 1,1,1,3,4-pentafluorobutane;1,1,1,4,4-pentafluorobutane; 1,1,2,2,3-pentafluorobutane;1,1,2,2,4-pentafluorobutane; 1,1,2,3,3-pentafluorobutane;1,1,2,4,4-pentafluorobutane; 1,1,3,3,4-pentafluorobutane;1,2,2,3,3-pentafluorobutane; 1,2,2,3,4-pentafluorobutane;1,1,1,2,2,3-hexafluorobutane; 1,1,1,2,2,4-hexafluorobutane;1,1,1,2,3,3-hexafluorobutane, 1,1,1,2,3,4-hexafluorobutane;1,1,1,2,4,4-hexafluorobutane; 1,1,1,3,3,4-hexafluorobutane;1,1,1,3,4,4-hexafluorobutane; 1,1,1,4,4,4-hexafluorobutane;1,1,2,2,3,3-hexafluorobutane; 1,1,2,2,3,4-hexafluorobutane;1,1,2,2,4,4-hexafluorobutane; 1,1,2,3,3,4-hexafluorobutane;1,1,2,3,4,4-hexafluorobutane; 1,2,2,3,3,4-hexafluorobutane;1,1,1,2,2,3,3-heptafluorobutane; 1,1,1,2,2,4,4-heptafluorobutane;1,1,1,2,2,3,4-heptafluorobutane; 1,1,1,2,3,3,4-heptafluorobutane;1,1,1,2,3,4,4-heptafluorobutane; 1,1,1,2,4,4,4-heptafluorobutane;1,1,1,3,3,4,4-heptafluorobutane; 1,1,1,2,2,3,3,4-octafluorobutane;1,1,1,2,2,3,4,4-octafluorobutane; 1,1,1,2,3,3,4,4-octafluorobutane;1,1,1,2,2,4,4,4-octafluorobutane; 1,1,1,2,3,4,4,4-octafluorobutane;1,1,1,2,2,3,3,4,4-nonafluorobutane; 1,1,1,2,2,3,4,4,4-nonafluorobutane;1-fluoro-2-methylpropane; 1,1-difluoro-2-methylpropane;1,3-difluoro-2-methylpropane; 1,1,1-trifluoro-2-methylpropane;1,1,3-trifluoro-2-methylpropane; 1,3-difluoro-2-(fluoromethyl)propane;1,1,1,3-tetrafluoro-2-methylpropane;1,1,3,3-tetrafluoro-2-methylpropane;1,1,3-trifluoro-2-(fluoromethyl)propane;1,1,1,3,3-pentafluoro-2-methylpropane;1,1,3,3-tetrafluoro-2-(fluoromethyl)propane;1,1,1,3-tetrafluoro-2-(fluoromethyl)propane; fluorocyclobutane;1,1-difluorocyclobutane; 1,2-difluorocyclobutane;1,3-difluorocyclobutane; 1,1,2-trifluorocyclobutane;1,1,3-trifluorocyclobutane; 1,2,3-trifluorocyclobutane;1,1,2,2-tetrafluorocyclobutane; 1,1,3,3-tetrafluorocyclobutane;1,1,2,2,3-pentafluorocyclobutane; 1,1,2,3,3-pentafluorocyclobutane;1,1,2,2,3,3-hexafluorocyclobutane; 1,1,2,2,3,4-hexafluorocyclobutane;1,1,2,3,3,4-hexafluorocyclobutane; 1,1,2,2,3,3,4-heptafluorocyclobutane.Particularly preferred HFC's include difluoromethane, trifluoromethane,1,1-difluoroethane, 1,1,1-trifluoroethane, fluoromethane, and1,1,1,2-tetrafluoroethane.

In other embodiments, one or more HFCs are used in combination withanother diluent or mixtures of diluents. Suitable additional diluentsinclude hydrocarbons, especially hexanes and heptanes, halogenatedhydrocarbons, especially chlorinated hydrocarbons and the like. Specificexamples include but are not limited to propane, isobutane, pentane,methycyclopentane, isohexane, 2-methylpentane, 3-methylpentane,2-methylbutane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methylhexane,3-methylhexane, 3-ethylpentane, 2,2-dimethylpentane,2,3-dimethylpentane, 2,4-dimethylpentane, 3,3-dimethyl pentane,2-methylheptane, 3-ethylhexane, 2,5-dimethylhexane,2,24,-trimethylpentane, octane, heptane, butane, ethane, methane,nonane, decane, dodecane, undecane, hexane, methyl cyclohexane,cyclopropane, cyclobutane, cyclopentane, methylcyclopentane,1,1-dimethylcyclopentane, c is 1,2-dimethylcyclopentane,trans-1,2-dimethylcyclopentane, trans-1,3-dimethylcyclopentane,ethylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene,xylene, ortho-xylene, para-xylene, meta-xylene, and the halogenatedversions of all of the above, preferably the chlorinated versions of theabove, more preferably fluorinated versions of all of the above.Brominated versions of the above are also useful. Specific examplesinclude, methyl chloride, methylene chloride, ethyl chloride, propylchloride, butyl chloride, chloroform and the like.

In one embodiment the HFC is used in combination with methyl chloride.Additional embodiments include using the HFC in combination with hexanesor methyl chloride and hexanes. In another embodiment the HFCs are usedin combination with one or more gases inert to the polymerization suchas carbon dioxide, nitrogen, argon, neon, helium, krypton, zenon, and/orother inert gases. Preferred gases include carbon dioxide and/ornitrogen.

In another embodiment, the HFCs are used in combination with one or morenitrated alkanes, including C₁ to C₄₀, preferably C₁ to C₂₀, morepreferably C₁ to C₁₂, and most preferably C₁ to C₈, alkanes, includingnitrated linear, cyclic or branched alkanes. Preferred nitrated alkanesinclude, but are not limited to, nitromethane, nitroethane,nitropropane, nitrobutane, nitropentane, nitrohexane, nitroheptane,nitrooctane, nitrodecane, nitrononane, nitrododecane, nitroundecane,nitrocyclomethane, nitrocycloethane, nitrocyclopropane,nitrocyclobutane, nitrocyclopentane, nitrocyclohexane,nitrocycloheptane, nitrocyclooctane, nitrocyclodecane, nitrocyclononane,nitrocyclododecane, nitrocycloundecane, nitrobenzene, and the di- andtri-nitro versions of the above. A preferred embodiment is HFCs blendedwith nitromethane.

The HFC is typically present at 1 to 100 volume % based upon the totalvolume of the diluents, alternatively between 5 and 100 volume %,alternatively between 10 and 100 volume %, alternatively between 15 and100 volume %, alternatively between 20 and 100 volume %, alternativelybetween 25 and 100 volume %, alternatively between 30 and 100 volume %,alternatively between 35 and 100 volume %, alternatively between 40 and100 volume %, alternatively between 45 and 100 volume %, alternativelybetween 50 and 100 volume %, alternatively between 55 and 100 volume %,alternatively between 60 and 100 volume %, alternatively between 65 and100 volume %, alternatively between 70 and 100 volume %, alternativelybetween 75 and 100 volume %, alternatively between 80 and 100 volume %,alternatively between 85 and 100 volume %, alternatively between 90 and100 volume %, alternatively between 95 and 100 volume %, alternativelybetween 97 and 100 volume %, alternatively between 98 and 100 volume %,and alternatively between 99 and 100 volume %. In another preferredembodiment the HFC is selected from the group consisting ofdifluoromethane, trifluoromethane, 1,1-difluoroethane,1,1,1-trifluoroethane, and 1,1,1,2-tetrafluoroethane and mixturesthereof.

In another preferred embodiment, the fluorinated hydrocarbon used in theprocess of the invention is selected from the group consisting ofdifluoromethane, trifluoromethane, 1,1-difluoroethane,1,1,1-trifluoroethane, and 1,1,1,2-tetrafluoroethane and mixturesthereof.

In one particularly preferred embodiment, the commercially availablefluorinated hydrocarbons useful in the process of the invention includeHFC-236fa having the chemical name 1,1,3,3,3-hexafluoropropane, HFC-134ahaving the chemical name 1,1,1,2-tetrafluoroethane, HFC-245fa having thechemical name 1,1,1,3,3-pentafluoropropane, HFC-365mfc having thechemical name 1,1,1,1,3,3-pentafluorobutane, R-318 having the chemicalname octafluorocyclobutane, and HFC-43-10mee having the chemical name2,3-dihydrodecafluoropentaineand/or HFC-365mfc, all of which arecommercially available fluorinated hydrocarbons.

In another embodiment, the fluorocarbon is not a perfluorinated C4 toC10 alkane. In another embodiment, the fluorocarbon is not aperfluorinated hydrocarbon. In another embodiment, the fluorocarbon isnot perfluorodecalin, perfluoroheptane, perfluorohexane,perfluoromethylcyclohexane, perfluorooctane,perfluoro-1,3-dimethylcyclohexane, perfluorononane, fluorobenzene, orperfluorotoluene. In a particularly preferred embodiment, thefluorocarbon consists essentially of hydrofluorocarbons.

In another embodiment the fluorocarbon is present at more than 1 weight%, based upon the weight of the fluorocarbon and any hydrocarbon solventpresent in the reactor, preferably greater than 3 weight %, preferablygreater than 5 weight %, preferably greater than 7 weight %, preferablygreater than 10 weight %, preferably greater than 15 weight %,preferably greater than 20 weight %, preferably greater than 25 weight%, preferably greater than 30 weight %, preferably greater than 35weight %, preferably greater than 40 weight %, preferably greater than50 weight %, preferably greater than 55 weight %, preferably greaterthan 60 weight %, preferably greater than 70 weight %, preferablygreater than 80 weight %, preferably greater than 90 weight %. Inanother embodiment the fluorocarbon is present at more than 1 weight %,based upon the weight of the fluorocarbons, monomers and any hydrocarbonsolvent present in the reactor, preferably greater than 3 weight %,preferably greater than 5 weight %, preferably greater than 7 weight %,preferably greater than 10 weight %, preferably greater than 15 weight%, preferably greater than 20 weight %, preferably greater than 25weight %, preferably greater than 30 weight %, preferably greater than35 weight %, preferably greater than 40 weight %, preferably greaterthan 50 weight %, preferably greater than 55 weight %, preferablygreater than 60 weight %, preferably greater than 70 weight %,preferably greater than 80 weight %, preferably greater than 90 weight%. In the event that the weight basis is not named for the weight %fluorocarbon, it shall be presumed to be based upon the total weight ofthe fluorocarbons, monomers and hydrocarbon solvents present in thereactor.

In another embodiment the fluorocarbon, preferably thehydrofluorocarbon, is present at more than 1 volume %, based upon thetotal volume of the fluorocarbon and any hydrocarbon solvent present inthe reactor, preferably greater than 3 volume %, preferably greater than5 volume %, preferably greater than 7 volume %, preferably greater than10 volume %, preferably greater than 15 volume %, preferably greaterthan 20 volume %, preferably greater than 25 volume %, preferablygreater than 30 volume %, preferably greater than 35 volume %,preferably greater than 40 volume %, preferably greater than 45 volume%, preferably greater than 50 volume %, preferably greater than 55volume %, preferably greater than 60 volume %, preferably greater than65 volume %.

In another embodiment the fluorocarbon is a blend of hydrofluorocarbonand perfluorocarbon and preferably the hydrofluorocarbon is present atmore than 1 volume %, based upon the total volume of the perfluorocarbonand the hydrofluorocarbon present in the reactor, (with the balancebeing made up by the perfluorocarbon) preferably greater than 3 volume%, preferably greater than 5 volume %, preferably greater than 7 volume%, preferably greater than 10 volume %, preferably greater than 15volume %, preferably greater than 20 volume %, preferably greater than25 volume %, preferably greater than 30 volume %, preferably greaterthan 35 volume %, preferably greater than 40 volume %, preferablygreater than 45 volume %, preferably greater than 50 volume %,preferably greater than 55 volume %, preferably greater than 60 volume%, preferably greater than 65 volume %.

In yet another embodiment, the fluorinated hydrocarbons of the inventionhave a molecular weight (MW) greater than 90 a.m.u., preferably greaterthan 95 a.m.u, and more preferably greater than 100 a.m.u. In anotherembodiment, the fluorinated hydrocarbons of the invention have a MWgreater than 120 a.m.u, preferably greater than 125 a.m.u, even morepreferably greater than 130 a.m.u, and most preferably greater than 140a.m.u. In still another embodiment, the fluorinated hydrocarbons of theinvention have a MW greater than 125 a.m.u, preferably greater than 130a.m.u, even more preferably greater than 135 a.m.u, and most preferablygreater than 150 a.m.u. In another embodiment, the fluorinatedhydrocarbons of the invention have a MW greater than 140 a.m.u,preferably greater than 150 a.m.u, more preferably greater than 180a.m.u, even more preferably greater than 200 a.m.u, and most preferablygreater than 225 a.m.u. In an embodiment, the fluorinated hydrocarbonsof the invention have a MW in the range of from 90 a.m.u to 1000 a.m.u,preferably in the range of from 100 a.m.u to 500 a.m.u, more preferablyin the range of from 100 a.m.u to 300 a.m.u, and most preferably in therange of from about 100 a.m.u to about 250 a.m.u.

In yet another embodiment, the fluorinated hydrocarbons of the inventionhave normal boiling point in the range of from about −50° C. up to thepolymerization temperature, preferably a polymerization temperature ofabout 85° C., preferably the normal boiling point of the fluorinatedhydrocarbons is in the range of from −40° C. to about 70° C., morepreferably from about −130° C. to about 60° C., and most preferably fromabout −30° C. to about 55° C. In an embodiment, the fluorinatedhydrocarbons of the invention have normal boiling point greater than−30° C., preferably greater than −30° C. to less than −10° C. In afurther embodiment, the fluorinated hydrocarbons of the invention havenormal boiling point greater than −5° C., preferably greater than −5° C.to less than −20° C. In one embodiment, the fluorinated hydrocarbons ofthe invention have normal boiling point greater than 30° C., preferablygreater than 30° C. to about 60° C.

In another embodiment, the fluorinated hydrocarbons of the inventionhave a liquid density @20° C. (g/cc) greater than 1 g/cc, preferablygreater than 1.10, and most preferably greater than 1.20 g/cc. In oneembodiment, the fluorinated hydrocarbons of the invention have a liquiddensity @20° C. (g/cc) greater than 1.20 g/cc, preferably greater than1.25, and most preferably greater than 1.30 g/cc. In an embodiment, thefluorinated hydrocarbons of the invention have a liquid density @20° C.(g/cc) greater than 1.30 g/cc, preferably greater than 1.40, and mostpreferably greater than 1.50 g/cc.

In one embodiment, the fluorinated hydrocarbons of the invention have aΔH Vaporization as measured by standard calorimetry techniques in therange between 100 kJ/kg to less than 300 kJ/kg, preferably in the rangeof from 110 kJ/kg to less than 300 kJ/kg, and most preferably in therange of from 120 kJ/kg to less than 300 kJ/kg.

In another preferred embodiment, the fluorinated hydrocarbons of theinvention have any combination of two or more of the aforementioned MW,normal boiling point, ΔH Vaporization, and liquid density values andranges. In a preferred embodiment, the fluorinated hydrocarbons usefulin the process of the invention have a MW greater than 90 a.m.u,preferably greater than 100 a.m.u, and a liquid density greater than1.00 g/cc, preferably greater than 1.20 g/cc. In yet another preferredembodiment, the fluorinated hydrocarbons useful in the process of theinvention have a liquid density greater than 1.10 g/cc, preferablygreater than 1.20 g/cc, and a normal boiling point greater than −50° C.,preferably greater than −30° C. up to the polymerization temperature ofthe process, which is as high as 100° C., preferably less than 85° C.,and more preferably less than 75° C., and most preferably less than 60°C. In one embodiment, the fluorinated hydrocarbons useful in the processof the invention have a MW greater than 90 a.m.u, preferably greaterthan 100 a.m.u, and a ΔH Vaporization in the range of from 100 kj/kg toless than 300 kj/kg, and optionally a liquid density greater than 1.00g/cc, preferably greater than 1.20 g/cc. In yet another embodiment, thefluorinated hydrocarbons useful in the process of the invention have aliquid density greater than 1.10 g/cc, preferably greater than 1.20g/cc, and a normal boiling point greater than −50° C., preferablygreater than −30° C. up to the polymerization temperature of theprocess, which is as high as 100° C., preferably less than 85° C., andmore preferably less than 75° C., and most preferably less than 60° C.,and optionally a ΔH Vaporization in the range of from 120 kj/kg to lessthan 250 kj/kg.

In yet another embodiment, one or more fluorinated hydrocarbon(s), aloneor in combination, with one or more other typical inert condensableagent(s) or condensing agent(s) are used in the process of theinvention. Examples of suitable, preferably inert, condensable agentsare readily volatile liquid hydrocarbons, which include, for example,saturated hydrocarbons containing from 1 to 8 carbon atoms, preferably 3to 8 carbon atoms, such as propane, n-butane, isobutane (MW of 58.12a.m.u, a liquid density of 0.55 g/cc, and normal boiling point as abovedescribed of −11.75), n-pentane, isopentane (MW of 72.15 a.m.u, a liquiddensity of 0.62 g/cc, and normal boiling point of 27.85), neopentane,n-hexane, isohexane, and other saturated C₆ to C₈ hydrocarbons.

In another embodiment, the diluent or diluent mixture is selected basedupon its solubility or lack thereof in a particular polymer beingproduced. Preferred diluents have little to no solubility in thepolymer. Solubility in the polymer is measured by forming the polymerinto a film of thickness between 50 and 100 microns, then soaking it indiluent (enough to cover the film) for 4 hours at the relevant desiredtemperature in a sealed container or vessel. The film is removed fromthe diluent, exposed for 90 seconds to evaporate excess condensablefluid from the surface of the film, and weighed. The mass uptake isdefined as the percentage increase in the film weight after soaking. Thediluent or diluent mixture is selected so that the polymer has a massuptake of less than 4 wt %, preferably less than 3 wt %, more preferablyless than 2 wt %, even more preferably less than 1 wt %, and mostpreferably less than 0.5 wt %.

In a preferred embodiment, the diluent(s) or mixtures thereof,preferably, the fluorinated hydrocarbon(s) or mixtures thereof, areselected such that the polymer melting temperature Tm is reduced (ordepressed) by not more than 15° C. by the presence of the condensablefluid. The depression of the polymer melting temperature ΔTm isdetermined by first measuring the melting temperature of a polymer bydifferential scanning calorimetry (DSC), and then comparing this to asimilar measurement on a sample of the same polymer that has been soakedwith the condensable fluid. In general, the melting temperature of thesoaked polymer will be lower than that of the dry polymer. Thedifference in these measurements is taken as the melting pointdepression ΔTm. It is well known to those in the art that higherconcentrations of dissolved materials in the polymer cause largerdepressions in the polymer melting temperature (i.e. higher values ofΔTm). A suitable DSC technique for determining the melting pointdepression is described by, P. V. Hemmingsen, “Phase Equilibria inPolyethylene Systems”, Ph.D Thesis, Norwegian University of Science andTechnology, March 2000, which is incorporated herein by reference. (Apreferred set of conditions for conducting the tests are summarized onPage 112 of this reference.) The polymer melting temperature is firstmeasured with dry polymer, and then repeated with the polymer immersedin liquid (the condensable fluid to be evaluated). As described in thereference above, it is important to ensure that the second part of thetest, conducted in the presence of the liquid, is done in a sealedcontainer so that the liquid is not flashed during the test, which couldintroduce experimental error. In one embodiment, the ΔTm of the diluent,especially the fluorinated hydrocarbon, is less than 12° C., preferablyless than 10° C., preferably less than 8° C., more preferably less than6° C., and most preferably less than 4° C. In another embodiment, themeasured ΔTm is less than 5° C., preferably less than 4° C., morepreferably less than 3° C., even more preferably less than 2° C., andmost preferably less than 1° C.

V. Catalyst System

A. Catalyst Compounds

The catalyst system of the invention will typically include a catalystcompound, and an activator compound, and may also include supportmaterials and one or more co-catalysts. The components of the catalystsystem are chosen to be capable of being utilized in the polymerizationprocess selected. For example, polymerization may be conducted in aslurry and/or in a solution where the slurry and solution are usedseparately or combined and introduced into a polymerization reactor. Thecatalyst compounds which may be utilized in the catalyst systems of theinvention for such polymerizations include: bulky ligand metallocenecompounds; transition metal catalysts (e.g., Ziegler Natta, Phillips);Group 15 containing metal compounds; phenoxide catalyst compounds; andadditionally discovered catalyst compounds. The catalysts, co-catalystsand activator compounds can include the support materials. As usedherein, the new notation numbering scheme for the Periodic Table Groupsare used as set out in Chemical And Engineering News, 63(5), 27 (1985).

In some embodiment, however, it is preferred that the catalyst systemnot comprise titanium tetrachloride, particularly not the combination ofTiCl₄ and aluminum alkyl (such as triethylaluminum), particularly whenthe FC is a perfluorocarbon. In situations where the catalyst istitanium tetrachloride, particularly the combination of TiCl₄ andaluminum alkyl (such as triethylaluminum) the FC is preferably ahydrofluorocarbon. In another embodiment, the catalyst is not a freeradical initiator, such as a peroxide.

1. Bulky Ligand Metallocenes

The catalyst compositions of the invention may include one or more bulkyligand metallocene compounds (also referred to herein as metallocenes).Typical bulky ligand metallocene compounds are generally described ascontaining one or more bulky ligand(s) and one or more leaving group(s)bonded to at least one metal atom. The bulky ligands are generallyrepresented by one or more open, acyclic, or fused ring(s) or ringsystem(s) or a combination thereof. These bulky ligands, preferably thering(s) or ring system(s) are typically composed of atoms selected fromGroups 13 to 16 atoms of the Periodic Table of Elements; preferably theatoms are selected from the group consisting of carbon, nitrogen,oxygen, silicon, sulfur, phosphorous, germanium, boron and aluminum or acombination thereof. Most preferably, the ring(s) or ring system(s) arecomposed of carbon atoms such as but not limited to thosecyclopentadienyl ligands or cyclopentadienyl-type ligand structures orother similar functioning ligand structure such as a pentadiene, acyclooctatetraendiyl or an imide ligand. The metal atom is preferablyselected from Groups 3 through 15 and the lanthamide or actinide seriesof the Periodic Table of Elements. Preferably the metal is a transitionmetal from Groups 4 through 12, more preferably Groups 4, 5 and 6, andmost preferably the transition metal is from Group 4.

In one embodiment, the catalyst composition of the invention includesone or more bulky ligand metallocene catalyst compounds represented bythe formula:L^(A)L^(B)MQ_(n)  (III)where M is a metal atom from the Periodic Table of the Elements and maybe a Group 3 to 12 metal or from the lanthamide or actinide series ofthe Periodic Table of Elements, preferably M is a Group 4, 5 or 6transition metal, more preferably M is a Group 4 transition metal, evenmore preferably M is zirconium, hafnium or titanium. The bulky ligands,L^(A) and L^(B), are open, acyclic or fused ring(s) or ring system(s)and are any ancillary ligand system, including unsubstituted orsubstituted, cyclopentadienyl ligands or cyclopentadienyl-type ligands,heteroatom substituted and/or heteroatom containingcyclopentadienyl-type ligands. Non-limiting examples of bulky ligandsinclude cyclopentadienyl ligands, cyclopentaphenanthreneyl ligands,indenyl ligands, benzindenyl ligands, fluorenyl ligands,octahydrofluorenyl ligands, cyclooctatetraendiyl ligands,cyclopentacyclododecene ligands, azenyl ligands, azulene ligands,pentalene ligands, phosphoyl ligands, phosphinimine (WO 99/40125),pyrrolyl ligands, pyrozolyl ligands, carbazolyl ligands, borabenzeneligands and the like, including hydrogenated versions thereof, forexample tetrahydroindenyl ligands. In one embodiment, L^(A) and L^(B)may be any other ligand structure capable of π-bonding to M. In yetanother embodiment, the atomic molecular weight (MW) of L^(A) or L^(B)exceeds 60 a.m.u., preferably greater than 65 a.m.u. In anotherembodiment, L^(A) and L^(B) may comprise one or more heteroatoms, forexample, nitrogen, silicon, boron, germanium, sulfur and phosphorous, incombination with carbon atoms to form an open, acyclic, or preferably afused, ring or ring system, for example, a hetero-cyclopentadienylancillary ligand. Other L^(A) and L^(B) bulky ligands include but arenot limited to bulky amides, phosphides, alkoxides, aryloxides, imides,carbolides, borollides, porphyrins, phthalocyanines, corrins and otherpolyazomacrocycles. Independently, each L^(A) and L^(B) may be the sameor different type of bulky ligand that is bonded to M. In one embodimentof Formula III only one of either L^(A) or L^(B) is present.

Independently, each L^(A) and L^(B) may be unsubstituted or substitutedwith a combination of substituent groups R. Non-limiting examples ofsubstituent groups R include one or more from the group selected fromhydrogen, or linear, branched alkyl radicals, or alkenyl radicals,alkynyl radicals, cycloalkyl radicals or aryl radicals, acyl radicals,aroyl radicals, alkoxy radicals, aryloxy radicals, alkylthio radicals,dialkylamino radicals, alkoxycarbonyl radicals, aryloxycarbonylradicals, carbomoyl radicals, alkyl- or dialkyl-carbamoyl radicals,acyloxy radicals, acylamino radicals, aroylamino radicals, straight,branched or cyclic, alkylene radicals, or combination thereof. In apreferred embodiment, substituent groups R have up to 50 non-hydrogenatoms, preferably from 1 to 30 carbon, that can also be substituted withhalogens or heteroatoms or the like. Non-limiting examples of alkylsubstituents R include methyl, ethyl, propyl, butyl, pentyl, hexyl,cyclopentyl, cyclohexyl, benzyl or phenyl groups and the like, includingall their isomers, for example tertiary butyl, isopropyl, and the like.Other hydrocarbyl radicals include fluoromethyl, fluoroethyl,difluoroethyl, iodopropyl, bromohexyl, chlorobenzyl and hydrocarbylsubstituted organometalloid radicals including trimethylsilyl,trimethylgermyl, methyldiethylsilyl and the like; andhalocarbyl-substituted organometalloid radicals includingtris(trifluoromethyl)-silyl, methyl-bis(difluoromethyl)silyl,bromomethyldimethylgermyl and the like; and disubstitiuted boronradicals including dimethylboron for example; and disubstitutedpnictogen radicals including dimethylamine, dimethylphosphine,diphenylamine, methylphenylphosphine, chalcogen radicals includingmethoxy, ethoxy, propoxy, phenoxy, methylsulfide and ethylsulfide.Non-hydrogen substituents R include the atoms carbon, silicon, boron,aluminum, nitrogen, phosphorous, oxygen, tin, sulfur, germanium and thelike, including olefins such as but not limited to olefinicallyunsaturated substituents including vinyl-terminated ligands, for examplebut-3-phenyl, prop-2-phenyl, hex-5-phenyl and the like. Also, at leasttwo R groups, preferably two adjacent R groups, are joined to form aring structure having from 3 to 30 atoms selected from carbon, nitrogen,oxygen, phosphorous, silicon, germanium, aluminum, boron or acombination thereof. Also, a substituent group R group such as 1-butanylmay form a carbon sigma bond to the metal M.

Other ligands may be bonded to the metal M, such as at least one leavinggroup Q. In one embodiment, Q is a monoanionic labile ligand having asigma-bond to M. Depending on the oxidation state of the metal, thevalue for n is 0, 1 or 2 such that Formula III above represents aneutral bulky ligand metallocene catalyst compound.

Non-limiting examples of Q ligands include weak bases such as amines,phosphines, ethers, carboxylates, dienes, hydrocarbyl radicals havingfrom 1 to 20 carbon atoms, hydrides or halogens and the like or acombination thereof. In another embodiment, two or more Q's form a partof a fused ring or ring system. Other examples of Q ligands includethose substituents for R as described above and including cyclobutyl,cyclohexyl, heptyl, tolyl, trifluoromethyl, tetramethylene,pentamethylene, methylidene, methyoxy, ethyoxy, propoxy, phenoxy,bis(N-methylanilide), dimethylamide, dimethylphosphide radicals and thelike.

In another embodiment, the catalyst composition of the invention mayinclude one or more bulky ligand metallocene catalyst compounds whereL^(A) and L^(B) of Formula III are bridged to each other by at least onebridging group, A, as represented by Formula IV.L^(A)AL^(B)MQ_(n)  (IV)

The compounds of Formula IV are known as bridged, bulky ligandmetallocene catalyst compounds. L^(A), L^(B), M, Q and n are as definedabove. Non-limiting examples of bridging group A include bridging groupscontaining at least one Group 13 to 16 atom, often referred to as adivalent moiety such as but not limited to at least one of a carbon,oxygen, nitrogen, silicon, aluminum, boron, germanium and tin atom or acombination thereof. Preferably bridging group A contains a carbon,silicon or germanium atom, most preferably A contains at least onesilicon atom or at least one carbon atom. The bridging group A may alsocontain substituent groups R as defined above including halogens andiron. Non-limiting examples of bridging group A may be represented byR′₂C, R′₂Si, R′₂Si R′₂Si, R′₂Ge, R′P, where R′ is independently, aradical group which is hydride, hydrocarbyl, substituted hydrocarbyl,halocarbyl, substituted halocarbyl, hydrocarbyl-substitutedorganometalloid, halocarbyl-substituted organometalloid, disubstitutedboron, disubstituted pnictogen, substituted chalcogen, or halogen or twoor more R′ may be joined to form a ring or ring system. In oneembodiment, the bridged, bulky ligand metallocene catalyst compounds ofFormula IV have two or more bridging groups A (EP 664 301 B1).

In another embodiment, the bulky ligand metallocene catalyst compoundsare those where the R substituents on the bulky ligands L^(A) and L^(B)of Formulas III and IV are substituted with the same or different numberof substituents on each of the bulky ligands. In another embodiment, thebulky ligands L^(A) and L^(B) of Formulas III and IV are different fromeach other.

Other bulky ligand metallocene catalyst compounds and catalyst systemsuseful in the invention may include those described in U.S. Pat. Nos.5,064,802, 5,145,819, 5,149,819, 5,243,001, 5,239,022, 5,276,208,5,296,434, 5,321,106, 5,329,031, 5,304,614, 5,677,401, 5,723,398,5,753,578, 5,854,363, 5,856,547 5,858,903, 5,859,158, 5,900,517 and5,939,503 and PCT publications WO 93/08221, WO 93/08199, WO 95/07140, WO98/11144, WO 98/41530, WO 98/41529, WO 98/46650, WO 99/02540 and WO99/14221 and European publications EP-A-0 578 838, EP-A-0 638 595,EP-B-0 513 380, EP-A1-0 816 372, EP-A2-0 839 834, EP-B1-0 632 819,EP-B1-0 748 821 and EP-B1-0 757 996, all of which are herein fullyincorporated by reference.

In another embodiment, the catalyst compositions of the invention mayinclude bridged heteroatom, mono-bulky ligand metallocene compounds.These types of catalysts and catalyst systems are described in, forexample, PCT publication WO 92/00333, WO 94/07928, WO 91/04257, WO94/03506, WO96/00244, WO 97/15602 and WO 99/20637 and U.S. Pat. Nos.5,057,475, 5,096,867, 5,055,438, 5,198,401, 5,227,440 and 5,264,405 andEuropean publication EP-A-0 420 436, all of which are herein fullyincorporated by reference.

In another embodiment, the catalyst composition of the inventionincludes one or more bulky ligand metallocene catalyst compoundsrepresented by Formula V:L^(C)AJMQ_(n)  (V)where M is a Group 3 to 16 metal atom or a metal selected from the Groupof actinides and lanthanides of the Periodic Table of Elements,preferably M is a Group 4 to 12 transition metal, and more preferably Mis a Group 4, 5 or 6 transition metal, and most preferably M is a Group4 transition metal in any oxidation state, especially titanium; L^(C) isa substituted or unsubstituted bulky ligand bonded to M; J is bonded toM; A is bonded to J and L^(C); J is a heteroatom ancillary ligand; and Ais a bridging group; Q is a univalent anionic ligand; and n is theinteger 0, 1 or 2. In Formula V above, L^(C), A and J form a fused ringsystem. In an embodiment, L^(C) of Formula V is as defined above forL^(A). A, M and Q of Formula V are as defined above in Formula III.

In Formula V J is a heteroatom containing ligand in which J is anelement with a coordination number of three from Group 15 or an elementwith a coordination number of two from Group 16 of the Periodic Table ofElements. Preferably J contains a nitrogen, phosphorus, oxygen or sulfuratom with nitrogen being most preferred. In a preferred embodiment, whenthe catalyst system comprises compounds represented by Formula V, thefluorocarbon preferably is a hydrofluorocarbon. Preferably, when thecatalyst system comprises compounds represented by Formula V, thefluorocarbon is not a perfluorocarbon.

In an embodiment of the invention, the bulky ligand metallocene catalystcompounds are heterocyclic ligand complexes where the bulky ligands, thering(s) or ring system(s), include one or more heteroatoms or acombination thereof. Non-limiting examples of heteroatoms include aGroup 13 to 16 element, preferably nitrogen, boron, sulfur, oxygen,aluminum, silicon, phosphorous and tin. Examples of these bulky ligandmetallocene catalyst compounds are described in WO 96/33202, WO96/34021, WO 97/17379 and WO 98/22486 and EP-A1-0 874 005 and U.S. Pat.Nos. 5,637,660, 5,539,124, 5,554,775, 5,756,611, 5,233,049, 5,744,417,and 5,856,258 all of which are herein incorporated by reference.

In one embodiment, the bulky ligand metallocene catalyst compounds arethose complexes known as transition metal catalysts based on bidentateligands containing pyridine or quinoline moieties, such as thosedescribed in U.S. application Ser. No. 09/103,620 filed Jun. 23, 1998,which is herein incorporated by reference. In another embodiment, thebulky ligand metallocene catalyst compounds are those described in PCTpublications WO 99/01481 and WO 98/42664, which are fully incorporatedherein by reference.

In another embodiment, the bulky ligand metallocene catalyst compound isa complex of a metal, preferably a transition metal, a bulky ligand,preferably a substituted or unsubstituted pi-bonded ligand, and one ormore heteroallyl moieties, such as those described in U.S. Pat. Nos.5,527,752 and 5,747,406 and EP-B1-0 735 057, all of which are hereinfully incorporated by reference.

In another embodiment, the catalyst composition of the inventionincludes one or more bulky ligand metallocene catalyst compounds isrepresented by Formula VI:L^(D)MQ₂(YZ)X_(n)  (VI)where M is a Group 3 to 16 metal, preferably a Group 4 to 12 transitionmetal, and most preferably a Group 4, 5 or 6 transition metal; L^(D) isa bulky ligand that is bonded to M; each Q is independently bonded to Mand Q₂(YZ) forms a ligand, preferably a unicharged polydentate ligand;or Q is a univalent anionic ligand also bonded to M; X is a univalentanionic group when n is 2 or X is a divalent anionic group when n is 1;n is 1 or 2.

In Formula VI, L and M are as defined above for Formula III. Q is asdefined above for Formula III, preferably Q is selected from the groupconsisting of —O—, —NR—, —CR2— and —S—; Y is either C or S; Z isselected from the group consisting of —OR, —NR2, —CR3, —SR, —SiR3, —PR2,—H, and substituted or unsubstituted aryl groups, with the proviso thatwhen Q is —NR— then Z is selected from one of the group consisting of—OR, —NR2, —SR, —SiR3, —PR2 and —H; R is selected from a groupcontaining carbon, silicon, nitrogen, oxygen, and/or phosphorus,preferably where R is a hydrocarbon group containing from 1 to 20 carbonatoms, most preferably an alkyl, cycloalkyl, or an aryl group; n is aninteger from 1 to 4, preferably 1 or 2; X is a univalent anionic groupwhen n is 2 or X is a divalent anionic group when n is 1; preferably Xis a carbamate, carboxylate, or other heteroallyl moiety described bythe Q, Y and Z combination.

In another embodiment, the bulky ligand metallocene catalyst compoundsare those described in PCT publications WO 99/01481 and WO 98/42664,which are fully incorporated herein by reference.

Useful Group 6 bulky ligand metallocene catalyst systems are describedin U.S. Pat. No. 5,942,462, which is incorporated herein by reference.

Still other useful catalysts include those multinuclear metallocenecatalysts as described in WO 99/20665 and U.S. Pat. No. 6,010,794, andtransition metal metaaracyle structures described in EP 0 969 101 A2,which are herein incorporated herein by reference. Other metallocenecatalysts include those described in EP 0 950 667 A1, doublecross-linked metallocene catalysts (EP 0 970 074 A1), tetheredmetallocenes (EP 970 963 A2) and those sulfonyl catalysts described inU.S. Pat. No. 6,008,394, which are incorporated herein by reference.

It is also contemplated that in one embodiment the bulky ligandmetallocene catalysts, described above, include their structural oroptical or enantiomeric isomers (meso and racemic isomers, for examplesee U.S. Pat. No. 5,852,143, incorporated herein by reference) andmixtures thereof.

2. Transition Metal Compounds

In another embodiment, conventional-type transition metal catalysts maybe used in the practice of this invention. Conventional-type transitionmetal catalysts are those traditional Ziegler-Natta, vanadium andPhillips-type catalysts well known in the art. Such as, for exampleZiegler-Natta catalysts as described in Ziegler-Natta Catalysts andPolymerizations, John Boor, Academic Press, New York, 1979. Examples ofconventional-type transition metal catalysts are also discussed in U.S.Pat. Nos. 4,115,639, 4,077,904, 4,482,687, 4,564,605, 4,721,763,4,879,359 and 4,960,741, all of which are herein fully incorporated byreference. The conventional-type transition metal catalyst compoundsthat may be used in the present invention include transition metalcompounds from Groups 3 to 17, preferably 4 to 12, more preferably 4 to6 of the Periodic Table of Elements.

Preferred conventional-type transition metal catalysts may berepresented by the formula: MR_(x), where M is a metal from Groups 3 to17, preferably Group 4 to 6, more preferably Group 4, most preferablytitanium; R is a halogen or a hydrocarbyloxy group; and x is theoxidation state of the metal M. Non-limiting examples of R includealkoxy, phenoxy, bromide, chloride and fluoride. Non-limiting examplesof conventional-type transition metal catalysts where M is titaniuminclude TiCl₄, TiBr₄, Ti(OC₂H₅)₃Cl, Ti(OC₂H₅)Cl₃, Ti(OC₄H₉)₃Cl,Ti(OC₃H₇)₂Cl₂, Ti(OC₂H₅)₂Br₂, TiCl₃.¹/₃AlCl₃ and Ti(OC₁₂H₂₅)Cl₃.

Conventional-type transition metal catalyst compounds based onmagnesium/titanium electron-donor complexes that are useful in theinvention are described in, for example, U.S. Pat. Nos. 4,302,565 and4,302,566, which are herein fully incorporate by reference. The MgTiCl₆(ethyl acetate)₄ derivative is particularly preferred.

British Patent Application 2,105,355 and U.S. Pat. No. 5,317,036, hereinincorporated by reference, describes various conventional-type vanadiumcatalyst compounds. Non-limiting examples of conventional-type vanadiumcatalyst compounds include vanadyl trihalide, alkoxy halides andalkoxides such as VOCl₃, VOCl₂(OBu) where Bu=butyl and VO(OC₂H₅)₃;vanadium tetra-halide and vanadium alkoxy halides such as VCl₄ andVCl₃(OBu); vanadium and vanadyl acetyl acetonates and chloroacetylacetonates such as V(AcAc)₃ and VOCl₂(AcAc) where (AcAc) is an acetylacetonate. The preferred conventional-type vanadium catalyst compoundsare VOCl₃, VCl₄ and VOCl₂—OR where R is a hydrocarbon radical,preferably a C₁ to C₁₀ aliphatic or aromatic hydrocarbon radical such asethyl, phenyl, isopropyl, butyl, propyl, n-butyl, iso-butyl,tertiary-butyl, hexyl, cyclohexyl, naphthyl, etc., and vanadium acetylacetonates.

Conventional-type chromium catalyst compounds, often referred to asPhillips-type catalysts, suitable for use in the present inventioninclude CrO₃, chromocene, silyl chromate, chromyl chloride (CrO₂Cl₂),chromium-2-ethyl-hexanoate, chromium acetylacetonate (Cr(AcAc)₃), andthe like. Non-limiting examples are disclosed in U.S. Pat. Nos.3,709,853, 3,709,954, 3,231,550, 3,242,099 and 4,077,904, which areherein fully incorporated by reference. Still other conventional-typetransition metal catalyst compounds and catalyst systems suitable foruse in the present invention are disclosed in U.S. Pat. Nos. 4,124,532,4,302,565, 4,302,566, 4,376,062, 4,379,758, 5,066,737, 5,763,723,5,849,655, 5,852,144, 5,854,164 and 5,869,585 and published EP-A2 0 416815 A2 and EP-A10 420 436, which are all herein incorporated byreference.

Other catalysts may include cationic catalysts such as AlCl₃, and othercobalt, iron, nickel and palladium catalysts well known in the art. Seefor example U.S. Pat. Nos. 3,487,112, 4,472,559, 4,182,814 and4,689,437, all of which are incorporated herein by reference.

It is also contemplated that other catalysts can be combined with thecatalyst compounds in the catalyst composition of the invention. Forexample, see U.S. Pat. Nos. 4,937,299, 4,935,474, 5,281,679, 5,359,015,5,470,811, and 5,719,241 all of which are herein fully incorporatedherein reference.

It is further contemplated that one or more of the catalyst compoundsdescribed above or catalyst systems may be used in combination with oneor more conventional catalyst compounds or catalyst systems.Non-limiting examples of mixed catalysts and catalyst systems aredescribed in U.S. Pat. Nos. 4,159,965, 4,325,837, 4,701,432, 5,124,418,5,077,255, 5,183,867, 5,391,660, 5,395,810, 5,691,264, 5,723,399 and5,767,031 and PCT Publication WO 96/23010 published Aug. 1, 1996, all ofwhich are herein fully incorporated by reference.

3. Group 15 Catalysts

In one embodiment, the catalyst compounds utilized in the inventioninclude: one or more Group 15 containing metal catalyst compounds. TheGroup 15 containing compound generally includes a Group 3 to 14 metalatom, preferably a Group 3 to 7, more preferably a Group 4 to 6, andeven more preferably a Group 4 metal atom, bound to at least one leavinggroup and also bound to at least two Group 15 atoms, at least one ofwhich is also bound to a Group 15 or 16 atom through another group.

In one embodiment, at least one of the Group 15 atoms is also bound to aGroup 15 or 16 atom through another group which may be a C₁ to C₂₀hydrocarbon group, a heteroatom containing group, silicon, germanium,tin, lead, or phosphorus, wherein the Group 15 or 16 atom may also bebound to nothing or a hydrogen, a Group 14 atom containing group, ahalogen, or a heteroatom containing group, and wherein each of the twoGroup 15 atoms are also bound to a cyclic group and may optionally bebound to hydrogen, a halogen, a heteroatom or a hydrocarbyl group, or aheteroatom containing group.

In another embodiment, the Group 15 containing metal compound of thepresent invention may be represented by the formulae:

wherein:

-   M is a Group 3 to 12 transition metal or a Group 13 or 14 main group    metal, preferably a Group 4, 5, or 6 metal, and more preferably a    Group 4 metal, and most preferably zirconium, titanium or hafnium;-   X is independently a leaving group, preferably, an anionic leaving    group, and more preferably hydrogen, a hydrocarbyl group, a    heteroatom or a halogen, and most preferably an alkyl;-   y is 0 or 1 (when y is 0 group L′ is absent);-   n is the oxidation state of M, preferably +3, +4, or +5, and more    preferably +4;-   m is the formal charge of the YZL or the YZL′ ligand, preferably 0,    −1, −2 or −3, and more preferably −2;-   L is a Group 15 or 16 element, preferably nitrogen;-   L′ is a Group 15 or 16 element or Group 14 containing group,    preferably carbon, silicon or germanium;-   Y is a Group 15 element, preferably nitrogen or phosphorus, and more    preferably nitrogen;-   Z is a Group 15 element, preferably nitrogen or phosphorus, and more    preferably nitrogen;-   R¹ and R² are independently a C₁ to C₂₀ hydrocarbon group, a    heteroatom containing group having up to twenty carbon atoms,    silicon, germanium, tin, lead, or phosphorus, preferably a C₂ to C₂₀    alkyl, aryl or aralkyl group, more preferably a linear, branched or    cyclic C₂ to C₂₀ alkyl group, most preferably a C₂ to C₆ hydrocarbon    group, wherein R¹ and R² may also be interconnected to each other;-   R³ is absent or a hydrocarbon group, hydrogen, a halogen, a    heteroatom containing group, preferably a linear, cyclic or branched    alkyl group having 1 to 20 carbon atoms, more preferably R³ is    absent, hydrogen or an alkyl group, and most preferably hydrogen;-   R⁴ and R⁵ are independently an alkyl group, an aryl group,    substituted aryl group, a cyclic alkyl group, a substituted cyclic    alkyl group, a cyclic aralkyl group, a substituted cyclic aralkyl    group or multiple ring system, preferably having up to 20 carbon    atoms, more preferably between 3 and 10 carbon atoms, and even more    preferably a C₁ to C₂₀ hydrocarbon group, a C₁ to C₂₀ aryl group or    a C₁ to C₂₀ aralkyl group, or a heteroatom containing group, for    example PR₃, where R is an alkyl group;-   R¹ and R² may be interconnected to each other, and/or R⁴ and R⁵ may    be interconnected to each other;-   R⁶ and R⁷ are independently absent, hydrogen, an alkyl group,    halogen, heteroatom, or a hydrocarbyl group, preferably a linear,    cyclic or branched alkyl group having 1 to 20 carbon atoms, and more    preferably absent; and-   R* is absent, or is hydrogen, a Group 14 atom containing group, a    halogen, or a heteroatom containing group.    By “formal charge of the YZL or YZL′ ligand”, it is meant the charge    of the entire ligand absent the metal and the leaving groups X.

By “R¹ and R² may also be interconnected” it is meant that R¹ and R² maybe directly bound to each other or may be bound to each other throughother groups. By “R⁴ and R⁵ may also be interconnected” it is meant thatR⁴ and R⁵ may be directly bound to each other or may be bound to eachother through other groups.

An alkyl group may be linear, branched alkyl radicals, alkenyl radicals,alkynyl radicals, cycloalkyl radicals, aryl radicals, acyl radicals,aroyl radicals, alkoxy radicals, aryloxy radicals, alkylthio radicals,dialkylamino radicals, alkoxycarbonyl radicals, aryloxycarbonylradicals, carbomoyl radicals, alkyl- or dialkyl-carbamoyl radicals,acyloxy radicals, acylamino radicals, aroylamino radicals, straight,branched or cyclic, alkylene radicals, or combination thereof. Anaralkyl group is defined to be a substituted aryl group.

In a preferred embodiment R⁴ and R⁵ are independently a grouprepresented by the following formula:

wherein:

-   R⁸ to R¹² are each independently hydrogen, a C₁ to C₄₀ alkyl group,    a halide, a heteroatom, a heteroatom containing group containing up    to 40 carbon atoms, preferably a C₁ to C₂₀ linear or branched alkyl    group, preferably a methyl, ethyl, propyl or butyl group, any two R    groups may form a cyclic group and/or a heterocyclic group, wherein    the cyclic groups may be aromatic.

In a preferred embodiment of Formula 1, R⁹, R¹⁰ and R¹² areindependently a methyl, ethyl, propyl or butyl group (including allisomers). In another preferred embodiment, R⁹, R¹⁰ and R² are methylgroups, and R⁸ and R¹¹ are hydrogen.

In a particularly preferred embodiment R⁴ and R⁵ are both a grouprepresented by the following formula:

In this embodiment, M is a Group 4 metal, preferably zirconium, titaniumor hafnium, and even more preferably zirconium; each of L, Y, and Z isnitrogen; each of R¹ and R² is —CH₂—CH₂—; R³ is hydrogen; and R⁶ and R⁷are absent.

In another particularly preferred embodiment, the Group 15 containingmetal compound is represented by Compound 1 below:

wherein Ph in Compound 1 equals phenyl.

The Group 15 containing metal compounds utilized in the catalystcomposition of the invention are prepared by methods known in the art,such as those disclosed in EP 0 893 454 A1, U.S. Pat. No. 5,889,128 andthe references cited in U.S. Pat. No. 5,889,128 which are all hereinincorporated by reference. U.S. application Ser. No. 09/312,878, filedMay 17, 1999, discloses a gas or slurry phase polymerization processusing a supported bisamide catalyst, which is also incorporated hereinby reference.

A preferred direct synthesis of these compounds comprises reacting theneutral ligand, (see for example YZL or YZL′ of formula I or II) withM^(n)X_(n) (M is a Group 3 to 14 metal, n is the oxidation state of M,each X is an anionic group, such as halide, in a non-coordinating orweakly coordinating solvent, such as ether, toluene, xylene, benzene,methylene chloride, and/or hexane or other solvent having a boilingpoint above 60° C., at about 20 to about 150° C. (preferably 20 to 100°C.), preferably for 24 hours or more, then treating the mixture with anexcess (such as four or more equivalents) of an alkylating agent, suchas methyl magnesium bromide in ether. The magnesium salts are removed byfiltration, and the metal complex isolated by standard techniques.

In one embodiment the Group 15 containing metal compound is prepared bya method comprising reacting a neutral ligand, (see for example YZL orYZL′ of formula I or II) with a compound represented by the formulaM^(n)X_(n) (where M is a Group 3 to 14 metal, n is the oxidation stateof M, each X is an anionic leaving group) in a non-coordinating orweakly coordinating solvent, at about 20° C. or above, preferably atabout 20 to about 100° C., then treating the mixture with an excess ofan alkylating agent, then recovering the metal complex. In a preferredembodiment the solvent has a boiling point above 60° C., such astoluene, xylene, benzene, and/or hexane. In another embodiment thesolvent comprises ether and/or methylene chloride, either beingpreferable.

For additional information of Group 15 containing metal compounds,please see Mitsui Chemicals, Inc. in EP 0 893 454 A1 which disclosestransition metal amides combined with activators to polymerize olefins.

In one embodiment the Group 15 containing metal compound is allowed toage prior to use as a polymerization. It has been noted on at least oneoccasion that one such catalyst compound (aged at least 48 hours)performed better than a newly prepared catalyst compound.

4. Phenoxides

The catalyst composition of the invention may include one or morephenoxide catalyst compounds represented by the following formulae:

wherein:

-   R¹ is hydrogen or a C₄ to C₁₀₀ group, preferably a tertiary alkyl    group, preferably a C₄ to C₂₀ alkyl group, preferably a C₄ to C₂₀    tertiary alkyl group, preferably a neutral C₄ to C₁₀₀ group and may    or may not also be bound to M;-   at least one of R² to R⁵ is a group containing a heteroatom, the    rest of R² to R⁵ are independently hydrogen or a C₁ to C₁₀₀ group,    preferably a C₄ to C₂₀ alkyl group (preferably butyl, isobutyl,    pentyl hexyl, heptyl, isohexyl, octyl, isooctyl, decyl, nonyl,    dodecyl) and any of R² to R⁵ also may or may not be bound to M;-   O is oxygen;-   M is a group 3 to group 10 transition metal or lanthamide metal,    preferably a group 4 metal, preferably Ti, Zr or Hf; and-   n is the valence state of the metal M, preferably 2, 3, 4, or 5, Q    is an alkyl, halogen, benzyl, amide, carboxylate, carbamate,    thiolate, hydride or alkoxide group, or a bond to an R group    containing a heteroatom which may be any of R¹ to R⁵.

A heteroatom containing group may be any heteroatom or a heteroatombound to carbon silica or another heteroatom. Preferred heteroatomsinclude boron, aluminum, silicon, nitrogen, phosphorus, arsenic, tin,lead, antimony, oxygen, selenium, tellurium. Particularly preferredheteroatoms include nitrogen, oxygen, phosphorus, and sulfur. Even moreparticularly preferred heteroatoms include oxygen and nitrogen. Theheteroatom itself may be directly bound to the phenoxide ring or it maybe bound to another atom or atoms that are bound to the phenoxide ring.The heteroatom containing group may contain one or more of the same ordifferent heteroatoms. Preferred heteroatom groups include imines,amines, oxides, phosphines, ethers, ketenes, oxoazolines heterocyclics,oxazolines, thioethers, and the like. Particularly preferred heteroatomgroups include imines. Any two adjacent R groups may form a ringstructure, preferably a 5 or 6 membered ring. Likewise the R groups mayform multi-ring structures. In one embodiment any two or more R groupsdo not form a 5 membered ring.

In a preferred embodiment, Q is a bond to any of R2 to R5, and the Rgroup that Q is bound to is a heteroatom containing group.

This invention may also be practiced with the catalysts disclosed in EP0 874 005 A1, which in incorporated by reference herein.

5. Additional Compounds

The catalyst compositions of the invention may include one or morecomplexes known as transition metal catalysts based on bidentate ligandscontaining pyridine or quinoline moieties, such as those described inU.S. Pat. No. 6,103,657, which is herein incorporated by reference.

In one embodiment, these catalyst compounds are represented by theformula:((Z)XA_(t)(YJ))_(q)MQ_(n)  (IX)where M is a metal selected from Group 3 to 13 or lanthamide andactinide series of the Periodic Table of Elements; Q is bonded to M andeach Q is a monovalent, bivalent, or trivalent anion; X and Y are bondedto M; one or more of X and Y are heteroatoms, preferably both X and Yare heteroatoms; Y is contained in a heterocyclic ring J, where Jcomprises from 2 to 50 non-hydrogen atoms, preferably 2 to 30 carbonatoms; Z is bonded to X, where Z comprises 1 to 50 non-hydrogen atoms,preferably 1 to 50 carbon atoms, preferably Z is a cyclic groupcontaining 3 to 50 atoms, preferably 3 to 30 carbon atoms; t is 0 or 1;when t is 1, A is a bridging group joined to at least one of X, Y or J,preferably X and J; q is 1 or 2; n is an integer from 1 to 4 dependingon the oxidation state of M. In one embodiment, where X is oxygen orsulfur then Z is optional. In another embodiment, where X is nitrogen orphosphorous then Z is present. In an embodiment, Z is preferably an arylgroup, more preferably a substituted aryl group.

It is within the scope of this invention, in one embodiment, thecatalyst compounds include complexes of Ni²⁺ and Pd²⁺ described in thearticles Johnson, et al., “New Pd(II)- and Ni(II)- Based Catalysts forPolymerization of Ethylene and a-Olefins”, J. Am. Chem. Soc. 1995, 117,6414-6415 and Johnson, et al., “Copolymerization of Ethylene andPropylene with Functionalized Vinyl Monomers by Palladium(II)Catalysts”, J. Am. Chem. Soc., 1996, 118, 267-268, and WO 96/23010published Aug. 1, 1996, WO 99/02472, U.S. Pat. Nos. 5,852,145, 5,866,663and 5,880,241, which are all herein fully incorporated by reference.These complexes can be either dialkyl ether adducts, or alkylatedreaction products of the described dihalide complexes that can beactivated to a cationic state by the activators of this inventiondescribed below.

Other catalyst compounds include those nickel complexes described in WO99/50313, which is incorporated herein by reference.

Also included are those diimine based ligands of Group 8 to 10 metalcatalyst compounds disclosed in PCT publications WO 96/23010 and WO97/48735 and Gibson, et al., Chem. Comm., pp. 849-850 (1998), all ofwhich are herein incorporated by reference.

Other useful catalyst compounds are those Group 5 and 6 metal imidocomplexes described in EP-A2-0 816 384 and U.S. Pat. No. 5,851,945,which is incorporated herein by reference. In addition, metallocenecatalysts include bridged bis(arylamido) Group 4 compounds described byD. H. McConville, et al., in Organometallics 1195, 14, 5478-5480, whichis herein incorporated by reference. In addition, bridged bis(amido)catalyst compounds are described in WO 96/27439, which is hereinincorporated by reference. Other useful catalysts are described asbis(hydroxy aromatic nitrogen ligands) in U.S. Pat. No. 5,852,146, whichis incorporated herein by reference. Other useful catalysts containingone or more Group 15 atoms include those described in WO 98/46651, whichis herein incorporated herein by reference.

B. Supports, Carriers and Techniques

In one embodiment, the catalyst composition of the invention includes asupport material or carrier, and preferably includes a supportedactivator. For example, the catalyst composition component, preferablythe activator compound and/or the catalyst compound, is deposited on,contacted with, vaporized with, bonded to, or incorporated within,adsorbed or absorbed in, or on, a support or carrier.

The support material is any of the conventional support materials.Preferably the supported material is a porous support material, forexample, talc, inorganic oxides and inorganic chlorides. Other supportmaterials include resinous support materials such as polystyrene,functionalized or crosslinked organic supports, such as polystyrenedivinyl benzene polyolefins or polymeric compounds, zeolites, clays, orany other organic or inorganic support material and the like, ormixtures thereof.

The preferred support materials are inorganic oxides that include thoseGroup 2, 3, 4, 5, 13 or 14 metal oxides. The preferred supports includesilica, which may or may not be dehydrated, fumed silica, alumina (WO99/60033), silica-alumina and mixtures thereof. Other useful supportsinclude magnesia, titania, zirconia, magnesium chloride (U.S. Pat. No.5,965,477), montmorillonite (European Patent EP-B1 0 511 665),phyllosilicate, zeolites, talc, clays (U.S. Pat. No. 6,034,187) and thelike. Also, combinations of these support materials may be used, forexample, silica-chromium, silica-alumina, silica-titania and the like.Additional support materials may include those porous acrylic polymersdescribed in EP 0 767 184 B1, which is incorporated herein by reference.Other support materials include nanocomposites as described in PCT WO99/47598, aerogels as described in WO 99/48605, spherulites as describedin U.S. Pat. No. 5,972,510 and polymeric beads as described in WO99/50311, which are all herein incorporated by reference.

It is preferred that the support material, most preferably an inorganicoxide, has a surface area in the range of from about 10 to about 700m2/g, pore volume in the range of from about 0.1 to about 4.0 cc/g andaverage particle size in the range of from about 5 to about 500 μm. Morepreferably, the surface area of the support material is in the range offrom about 50 to about 500 m2/g, pore volume of from about 0.5 to about3.5 cc/g and average particle size of from about 10 to about 200 μm.Most preferably the surface area of the support material is in the rangeis from about 100 to about 400 m2/g, pore volume from about 0.8 to about3.0 cc/g and average particle size is from about 5 to about 100 μm. Theaverage pore size of the carrier of the invention typically has poresize in the range of from 10 to 1000 Å, preferably 50 to about 500 Å,and most preferably 75 to about 350 Å.

The support materials may be treated chemically, for example with afluoride compound as described in WO 00/12565, which is hereinincorporated by reference. Other supported activators are described infor example WO 00/13792 that refers to supported boron containing solidacid complex.

In a preferred embodiment, fumed silica available under the trade nameCabosil™ TS-610, available from Cabot Corporation is utilized as anucleating agent or as a viscosity builder in the catalyst componentslurry discussed below. Fumed silica is typically a silica withparticles 7 to 30 nanometers in size that has been treated withdimethylsilyldichloride such that a majority of the surface hydroxylgroups are capped. In another embodiment the fumed silica utilized has aparticle size of less than 40 microns, preferably less than 20 micronsor preferably less than 10 microns.

In a preferred method of forming a supported catalyst compositioncomponent, the amount of liquid in which the activator is present is inan amount that is less than four times the pore volume of the supportmaterial, more preferably less than three times, even more preferablyless than two times; preferred ranges being from 1.1 times to 3.5 timesrange and most preferably in the 1.2 to 3 times range. In an alternativeembodiment, the amount of liquid in which the activator is present isfrom one to less than one times the pore volume of the support materialutilized in forming the supported activator.

Procedures for measuring the total pore volume of a porous support arewell known in the art. Details of one of these procedures is discussedin Volume 1, Experimental Methods in Catalytic Research (Academic Press,1968) (specifically see pages 67-96). This preferred procedure involvesthe use of a classical BET apparatus for nitrogen absorption. Anothermethod well known in the art is described in Innes, Total Porosity andParticle Density of Fluid Catalysts By Liquid Titration, Vol. 28, No. 3,Analytical Chemistry 332-334 (March, 1956).

C. Activators and Activation Methods

The polymerization catalyst compounds useful in this invention can beactivated in various ways to yield compounds having a vacantcoordination site that will coordinate, insert, and polymerizeolefin(s). For the purposes of this invention, the term “activator” isdefined to be any compound which can activate any one of the catalystcompounds described herein by converting the neutral catalyst compoundto a catalytically active catalyst cation compound. Non-limitingactivators, for example, include alumoxanes, aluminum alkyls, ionizingactivators, which may be neutral or ionic, and conventional-typecocatalysts.

1. Alumoxanes

In one embodiment, alumoxanes activators are utilized as an activator inthe catalyst composition of the invention. Alumoxanes are generallyoligomeric compounds containing —Al(R)—O— subunits, where R is an alkylgroup. Examples of alumoxanes include methylalumoxane (MAO), modifiedmethylalumoxane (MMAO), ethylalumoxane and isobutylalumoxane. Alumoxanesmay be produced by the hydrolysis of the respective trialkylaluminumcompound. MMAO may be produced by the hydrolysis of trimethylaluminumand a higher trialkylaluminum such as triisobutylaluminum. MMAO's aregenerally more soluble in aliphatic solvents and more stable duringstorage. There are a variety of methods for preparing alumoxane andmodified alumoxanes, non-limiting examples of which are described inU.S. Pat. Nos. 4,665,208, 4,952,540, 5,091,352, 5,206,199, 5,204,419,4,874,734, 4,924,018, 4,908,463, 4,968,827, 5,308,815, 5,329,032,5,248,801, 5,235,081, 5,157,137, 5,103,031, 5,391,793, 5,391,529,5,693,838, 5,731,253, 5,731,451, 5,744,656, 5,847,177, 5,854,166,5,856,256 and 5,939,346 and European publications EP-A-0 561 476,EP-B1-0 279 586, EP-A-0 594-218 and EP-B1-0 586 665, and PCTpublications WO 94/10180 and WO 99/15534, all of which are herein fullyincorporated by reference. Another alumoxane is a modified methylalumoxane (MMAO) cocatalyst type 3A (commercially available from AkzoChemicals, Inc. under the trade name Modified Methylalumoxane type 3A,covered under patent number U.S. Pat. No. 5,041,584).

Aluminum Alkyl or organoaluminum compounds which may be utilized asactivators include trimethylaluminum, triethylaluminum,triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum and thelike.

2. Ionizing Activators

It is within the scope of this invention to use an ionizing orstoichiometric activator, neutral or ionic, such as tri(n-butyl)ammonium tetrakis (pentafluorophenyl) boron, a trisperfluorophenyl boronmetalloid precursor or a trisperfluoronaphtyl boron metalloid precursor,polyhalogenated heteroborane anions (WO 98/43983), boric acid (U.S. Pat.No. 5,942,459) or combination thereof. It is also within the scope ofthis invention to use neutral or ionic activators alone or incombination with alumoxane or modified alumoxane activators.

Examples of neutral stoichiometric activators include tri-substitutedboron, tellurium, aluminum, gallium and indium or mixtures thereof. Thethree substituent groups are each independently selected from alkyls,alkenyls, halogen, substituted alkyls, aryls, arylhalides, alkoxy andhalides. Preferably, the three groups are independently selected fromhalogen, mono or multicyclic (including halosubstituted) aryls, alkyls,and alkenyl compounds and mixtures thereof, preferred are alkenyl groupshaving 1 to 20 carbon atoms, alkyl groups having 1 to 20 carbon atoms,alkoxy groups having 1 to 20 carbon atoms and aryl groups having 3 to 20carbon atoms (including substituted aryls). More preferably, the threegroups are alkyls having 1 to 4 carbon groups, phenyl, napthyl ormixtures thereof. Even more preferably, the three groups arehalogenated, preferably fluorinated, aryl groups. Most preferably, theneutral stoichiometric activator is trisperfluorophenyl boron ortrisperfluoronapthyl boron.

“Substituted alkyl” refers to an alkyl as described in which one or morehydrogen atoms of the alkyl is replaced by another group such as ahalogen, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, andcombinations thereof. Examples of substituted alkyls include, forexample, benzyl, trifluoromethyl and the like.

Ionic stoichiometric activator compounds may contain an active proton,or some other cation associated with, but not coordinated to, or onlyloosely coordinated to, the remaining ion of the ionizing compound. Suchcompounds and the like are described in European publications EP-A-0 570982, EP-A-0 520 732, EP-A-0 495 375, EP-B1-0 500 944, EP-A-0 277 003 andEP-A-0 277 004, and U.S. Pat. Nos. 5,153,157, 5,198,401, 5,066,741,5,206,197, 5,241,025, 5,384,299 and 5,502,124 and U.S. patentapplication Ser. No. 08/285,380, filed Aug. 3, 1994, all of which areherein fully incorporated by reference.

In a preferred embodiment, the stoichiometric activators include acation and an anion component, and may be represented by the followingformula:(L-H)_(d) ⁺.(A^(d−))  (X)wherein:L is an neutral Lewis base;H is hydrogen;(L-H)⁺ is a Bronsted acidA^(d−) is a non-coordinating anion having the charge d-d is an integer from 1 to 3.

The cation component, (L-H)_(d) ⁺ may include Bronsted acids such asprotons or protonated Lewis bases or reducible Catalysts capable ofprotonating or abstracting a moiety, such as an alkyl or aryl, from thebulky ligand metallocene or Group 15 containing transition metalcatalyst precursor, resulting in a cationic transition metal species.

The activating cation (L-H)_(d) ⁺ may be a Bronsted acid, capable ofdonating a proton to the transition metal catalytic precursor resultingin a transition metal cation, including ammoniums, oxoniums,phosphoniums, silyliums and mixtures thereof, preferably ammoniums ofmethylamine, aniline, dimethylamine, diethylamine, N-methylaniline,diphenylamine, trimethylamine, triethylamine, N,N-dimethylaniline,methyldiphenylamine, pyridine, p-bromo N,N-dimethylaniline,p-nitro-N,N-dimethylaniline, phosphoniums from triethylphosphine,triphenylphosphine, and diphenylphosphine, oxomiuns from ethers such asdimethyl ether diethyl ether, tetrahydrofuran and dioxane, sulfoniumsfrom thioethers, such as diethyl thioethers and tetrahydrothiophene andmixtures thereof. The activating cation (L-H)_(d) ⁺ may also be anabstracting moiety such as silver, carboniums, tropylium, carbeniums,ferroceniums and mixtures, preferably carboniums and ferroceniums. Mostpreferably (L-H)_(d) ⁺ is triphenyl carbonium.

The anion component A^(d−) includes those having the formula[M^(k+)Q_(n)]^(d−) wherein k is an integer from 1 to 3; n is an integerfrom 2-6; n−k=d; M is an element selected from Group 13 of the PeriodicTable of the Elements, preferably boron or aluminum, and Q isindependently a hydride, bridged or unbridged dialkylamido, halide,alkoxide, aryloxide, hydrocarbyl, substituted hydrocarbyl, halocarbyl,substituted halocarbyl, and halosubstituted-hydrocarbyl radicals, said Qhaving up to 20 carbon atoms with the proviso that in not more than 1occurrence is Q a halide. Preferably, each Q is a fluorinatedhydrocarbyl group having 1 to 20 carbon atoms, more preferably each Q isa fluorinated aryl group, and most preferably each Q is a pentafluorylaryl group. Examples of suitable A^(d−) also include diboron compoundsas disclosed in U.S. Pat. No. 5,447,895, which is fully incorporatedherein by reference.

Most preferably, the ionic stoichiometric activator (L-H)_(d) ⁺.(A^(d−))is N,N-dimethylanilinium tetra(perfluorophenyl)borate ortriphenylcarbenium tetra(perfluorophenyl)borate.

In one embodiment, an activation method using ionizing ionic compoundsnot containing an active proton but capable of producing a bulky ligandmetallocene catalyst cation and their non-coordinating anion are alsocontemplated, and are described in EP-A-0 426 637, EP-A-0 573 403 andU.S. Pat. No. 5,387,568, which are all herein incorporated by reference.

3. Additional Activators

Other activators include those described in PCT publication WO 98/07515such as tris(2,2′,2″-nonafluorobiphenyl)fluoroaluminate, whichpublication is fully incorporated herein by reference. Combinations ofactivators are also contemplated by the invention, for example,alumoxanes and ionizing activators in combinations, see for example,EP-B1 0 573 120, PCT publications WO 94/07928 and WO 95/14044 and U.S.Pat. Nos. 5,153,157 and 5,453,410 all of which are herein fullyincorporated by reference.

Other suitable activators are disclosed in WO 98/09996, incorporatedherein by reference, which describes activating bulky ligand metallocenecatalyst compounds with perchlorates, periodates and iodates includingtheir hydrates. WO 98/30602 and WO 98/30603, incorporated by reference,describe the use of lithium (2,2′-bisphenyl-ditrimethylsilicate).4THF asan activator for a bulky ligand metallocene catalyst compound. WO99/18135, incorporated herein by reference, describes the use oforgano-boron-aluminum acitivators. EP-B31-0 781 299 describes using asilylium salt in combination with a non-coordinating compatible anion.Also, methods of activation such as using radiation (see EP-B1-0 615 981herein incorporated by reference), electro-chemical oxidation, and thelike are also contemplated as activating methods for the purposes ofrendering the neutral bulky ligand metallocene catalyst compound orprecursor to a bulky ligand metallocene cation capable of polymerizingolefins. Other activators or methods for activating a bulky ligandmetallocene catalyst compound are described in for example, U.S. Pat.Nos. 5,849,852, 5,859,653 and 5,869,723 and WO 98/32775, WO 99/42467(dioctadecylmethylammonium-bis(tris(pentafluorophenyl)borane)benzimidazolide), which are herein incorporated by reference.

Another suitable ion forming, activating cocatalyst comprises a salt ofa cationic oxidizing agent and a noncoordinating, compatible anionrepresented by the formula: (OX^(e+))_(d)(A^(d−))_(e), wherein: OX^(e+)is a cationic oxidizing agent having a charge of e+; e is an integerfrom 1 to 3; and A⁻, and d are as previously defined. Examples ofcationic oxidizing agents include: ferrocenium, hydrocarbyl-substitutedferroceniumn, Ag⁺, or Pb⁺². Preferred embodiments of A^(d−) are thoseanions previously defined with respect to the Bronsted acid containingactivators, especially tetrakis(pentafluorophenyl)borate.

It within the scope of this invention that catalyst compounds can becombined one or more activators or activation methods described above.For example, a combination of activators have been described in U.S.Pat. Nos. 5,153,157 and 5,453,410, European publication EP-B1 0 573 120,and PCT publications WO 94/07928 and WO 95/14044. These documents alldiscuss the use of an alumoxane and an ionizing activator with a bulkyligand metallocene catalyst compound.

4. Supported Activators

Many supported activators are described in various patents andpublications which include: U.S. Pat. No. 5,728,855 directed to theforming a supported oligomeric alkylaluminoxane formed by treating atrialkylaluminum with carbon dioxide prior to hydrolysis; U.S. Pat. Nos.5,831,109 and 5,777,143 discusses a supported methylalumoxane made usinga non-hydrolytic process; U.S. Pat. No. 5,731,451 relates to a processfor making a supported alumoxane by oxygenation with a trialkylsiloxymoiety; U.S. Pat. No. 5,856,255 discusses forming a supported auxiliarycatalyst (alumoxane or organoboron compound) at elevated temperaturesand pressures; U.S. Pat. No. 5,739,368 discusses a process of heattreating alumoxane and placing it on a support; EP-A-0 545 152 relatesto adding a metallocene to a supported alumoxane and adding moremethylalumoxane; U.S. Pat. Nos. 5,756,416 and 6,028,151 discuss acatalyst composition of a alumoxane impregnated support and ametallocene and a bulky aluminum alkyl and methylalumoxane; EP-B1-0 662979 discusses the use of a metallocene with a catalyst support of silicareacted with alumoxane; PCT WO 96/16092 relates to a heated supporttreated with alumoxane and washing to remove unfixed alumoxane; U.S.Pat. Nos. 4,912,075, 4,937,301, 5,008,228, 5,086,025, 5,147,949,4,871,705, 5,229,478, 4,935,397, 4,937,217 and 5,057,475, and PCT WO94/26793 all directed to adding a metallocene to a supported activator;U.S. Pat. No. 5,902,766 relates to a supported activator having aspecified distribution of alumoxane on the silica particles; U.S. Pat.No. 5,468,702 relates to aging a supported activator and adding ametallocene; U.S. Pat. No. 5,968,864 discusses treating a solid withalumoxane and introducing a metallocene; EP 0 747 430 A1 relates to aprocess using a metallocene on a supported methylalumoxane andtrimethylaluminum; EP 0 969 019 A1 discusses the use of a metalloceneand a supported activator; EP-B2-0 170 059 relates to a polymerizationprocess using a metallocene and a organo-aluminuim compound, which isformed by reacting aluminum trialkyl with a water containing support;U.S. Pat. No. 5,212,232 discusses the use of a supported alumoxane and ametallocene for producing styrene based polymers; U.S. Pat. No.5,026,797 discusses a polymerization process using a solid component ofa zirconium compound and a water-insoluble porous inorganic oxidepreliminarily treated with alumoxane; U.S. Pat. No. 5,910,463 relates toa process for preparing a catalyst support by combining a dehydratedsupport material, an alumoxane and a polyfunctional organic crosslinker;U.S. Pat. Nos. 5,332,706, 5,473,028, 5,602,067 and 5,420,220 discusses aprocess for making a supported activator where the volume of alumoxanesolution is less than the pore volume of the support material; WO98/02246 discusses silica treated with a solution containing a source ofaluminum and a metallocene; WO 99/03580 relates to the use of asupported alumoxane and a metallocene; EP-A1-0 953 581 discloses aheterogeneous catalytic system of a supported alumoxane and ametallocene; U.S. Pat. No. 5,015,749 discusses a process for preparing apolyhydrocarbyl-alumoxane using a porous organic or inorganic imbibermaterial; U.S. Pat. Nos. 5,446,001 and 5,534,474 relates to a processfor preparing one or more alkylaluminoxanes immobilized on a solid,particulate inert support; and EP-A1-0 819 706 relates to a process forpreparing a solid silica treated with alumoxane. Also, the followingarticles, also fully incorporated herein by reference for purposes ofdisclosing useful supported activators and methods for theirpreparation, include: W. Kaminsky, et al., “Polymerization of Styrenewith Supported Half-Sandwich Complexes,” Journal of Polymer Science,Vol. 37, 2959-2968 (1999) describes a process of adsorbing amethylalumoxane to a support followed by the adsorption of ametallocene; Junting Xu, et al. “Characterization of isotacticpolypropylene prepared with dimethylsilyl bis(1-indenyl)zirconiumdichloride supported on methylaluminoxane pretreated silica,”EuropeanPolymer Journal, 35 (1999) 1289-1294, discusses the use of silicatreated with methylalumoxane and a metallocene; Stephen O'Brien, et al.,“EXAFS analysis of a chiral alkene polymerization catalyst incorporatedin the mesoporous silicate MCM-41,” Chem. Commun., 1905-1906 (1997)discloses an immobilized alumoxane on a modified mesoporous silica; andF. Bonini, et al., “Propylene Polymerization through SupportedMetallocene/MAO Catalysts: Kinetic Analysis and Modeling,” Journal ofPolymer Science, Vol. 33 2393-2402 (1995) discusses using amethylalumoxane supported silica with a metallocene. Any of the methodsdiscussed in these references are useful for producing the supportedactivator component utilized in the catalyst composition of theinvention and all are incorporated herein by reference.

In another embodiment, the supported activator, such as supportedalumoxane, is aged for a period of time prior to use herein. Forreference please refer to U.S. Pat. Nos. 5,468,702 and 5,602,217,incorporated herein by reference.

In an embodiment, the supported activator is in a dried state or asolid. In another embodiment, the supported activator is in asubstantially dry state or a slurry, preferably in a mineral oil slurry.

In another embodiment, two or more separately supported activators areused, or alternatively, two or more different activators on a singlesupport are used.

In another embodiment, the support material, preferably partially ortotally dehydrated support material, preferably 200° C. to 600° C.dehydrated silica, is then contacted with an organoaluminum or alumoxanecompound. Preferably in an embodiment where an organoaluminum compoundis used, the activator is formed in situ on and in the support materialas a result of the reaction of, for example, trimethylaluminum andwater.

In another embodiment, Lewis base-containing supports are reacted with acatalyst activator to form a support bonded catalyst compound. The Lewisbase hydroxyl groups of silica are exemplary of metal/metalloid oxideswhere this method of bonding to a support occurs. This embodiment isdescribed in U.S. Pat. No. 6,147,173, which is herein incorporated byreference.

Other embodiments of supporting an activator are described in U.S. Pat.No. 5,427,991, where supported non-coordinating anions derived fromtrisperfluorophenyl boron are described; U.S. Pat. No. 5,643,847discusses the reaction of Group 13 catalyst compounds with metal oxidessuch as silica and illustrates the reaction of trisperfluorophenyl boronwith silanol groups (the hydroxyl groups of silicon) resulting in boundanions capable of protonating transition metal organometallic catalystcompounds to form catalytically active cations counter-balanced by thebound anions; immobilized Group IIIA Catalyst catalysts suitable forcarbocationic polymerizations are described in U.S. Pat. No. 5,288,677;and James C. W. Chien, Jour. Poly. Sci.: Pt A: Poly. Chem., Vol. 29,1603-1607 (1991), describes the olefin polymerization utility ofmethylalumoxane (MAO) reacted with silica (SiO₂) and metallocenes anddescribes a covalent bonding of the aluminum atom to the silica throughan oxygen atom in the surface hydroxyl groups of the silica.

In a preferred embodiment, a supported activator is formed by preparingin an agitated, and temperature and pressure controlled vessel asolution of the activator and a suitable solvent, then adding thesupport material at temperatures from 0° C. to 100° C., contacting thesupport with the activator solution for up to 24 hours, then using acombination of heat and pressure to remove the solvent to produce a freeflowing powder. Temperatures can range from 40 to 120° C. and pressuresfrom 5 psia to 20 psia (34.5 to 138 kPa). An inert gas sweep can also beused in assist in removing solvent. Alternate orders of addition, suchas slurrying the support material in an appropriate solvent then addingthe activator, can be used.

In another embodiment a support is combined with one or more activatorsand is spray dried to form a supported activator. In a preferredembodiment, fumed silica is combined with methyl alumoxane and thenspray dried to from supported methyl alumoxane. Preferably a support iscombined with alumoxane, spray dried and then placed in mineral oil toform a slurry useful in the instant invention.

D. Cocatalysts

Cocatalysts that can be used according to this invention include one ormore cocatalysts represented by the formula:M³M⁴ _(v)X² _(c)R³ _(b-c),wherein M³ is a metal from Group 1 to 3 and 12 to 13 of the PeriodicTable of Elements; M⁴ is a metal of Group 1 of the Periodic Table ofElements; v is a number from 0 to 1; each X² is any halogen; c is anumber from 0 to 3; each R³ is a monovalent hydrocarbon radical orhydrogen; b is a number from 1 to 4; and wherein b minus c is atleast 1. Other conventional-type organometallic cocatalyst compounds forthe above conventional-type transition metal catalysts have the formulaM³R³ _(k), where M³ is a Group IA, IIA, IIB or IIIA metal, such aslithium, sodium, beryllium, barium, boron, aluminum, zinc, cadmium, andgallium; k equals 1, 2 or 3 depending upon the valency of M³ whichvalency in turn normally depends upon the particular Group to which M³belongs; and each R³ may be any monovalent hydrocarbon radical.

Non-limiting examples of conventional-type organometallic cocatalystcompounds useful with the conventional-type catalyst compounds describedabove include methyllithium, butyllithium, dihexylmercury,butylmagnesium, diethylcadmium, benzylpotassium, diethylzinc,tri-n-butylaluminum, diisobutyl ethylboron, diethylcadmium,di-n-butylzinc and tri-n-amylboron, and, in particular, the aluminumalkyls, such as tri-hexyl-aluminum, triethylaluminum, trimethylaluminum,and tri-isobutylaluminum. Other conventional-type cocatalyst compoundsinclude mono-organohalides and hydrides of Group 2 metals, and mono- ordi-organohalides and hydrides of Group 3 and 13 metals. Non-limitingexamples of such conventional-type cocatalyst compounds includedi-isobutylaluminum bromide, isobutylboron dichloride, methyl magnesiumchloride, ethylberyllium chloride, ethylcalcium bromide,di-isobutylaluminum hydride, methylcadmium hydride, diethylboronhydride, hexylberyllium hydride, dipropylboron hydride, octylmagnesiumhydride, butylzinc hydride, dichloroboron hydride, di-bromo-aluminumhydride and bromocadmium hydride. Conventional-type organometalliccocatalyst compounds are known to those in the art and a more completediscussion of these compounds may be found in U.S. Pat. Nos. 3,221,002and 5,093,415, which are herein fully incorporated by reference.

E. Spray Dried Catalysts

In another embodiment, the catalyst compounds described are combinedwith support material(s) and/or activator(s) and spray dried. In anotherembodiment, the catalyst compounds and/or the activators are combinedwith a support material such as a particulate filler material and thenspray dried, preferably to form a free flowing powder.

Spray drying may be by any means known in the art. Please see EP A 0 668295 B1, U.S. Pat. No. 5,674,795 and U.S. Pat. No. 5,672,669 and U.S.patent application Ser. No. 09/464,114 filed Dec. 16, 1999, whichparticularly describe spray drying of supported catalysts. In generalone may spray dry the catalysts by placing the catalyst compound and theoptional activator in solution (allowing the catalyst compound andactivator to react, if desired), adding a filler material such as silicaor fumed silica, such as Gasil™ or Cabosil™, then forcing the solutionat high pressures through a nozzle. The solution may be sprayed onto asurface or sprayed such that the droplets dry in midair. The methodgenerally employed is to disperse the silica in toluene, stir in theactivator solution, and then stir in the catalyst compound solution.Typical slurry concentrations are about 5 to 8 wt %. This formulationmay sit as a slurry for as long as 30 minutes with mild stirring ormanual shaking to keep it as a suspension before spray-drying. In onepreferred embodiment, the makeup of the dried material is about 40-50 wt% activator (preferably alumoxane), 50-60 SiO₂ and about ˜2 wt %catalyst compound.

In another embodiment, fumed silica such as such as Gasil™ or Cabosil™may be added to a solution containing a catalyst compound such that whenthat solution is added to the catalyst component slurry or injected intoa polymerization reactor, the fumed silica acts as a template for “insitu spray” drying.

For simple catalyst compound mixtures, the two or more catalystcompounds can be added together in the desired ratio in the last step.In another embodiment, more complex procedures are possible, such asaddition of a first catalyst compound to the activator/filler mixturefor a specified reaction time t, followed by the addition of the secondcatalyst compound solution, mixed for another specified time x, afterwhich the mixture is cosprayed. Lastly, another additive, such as1-hexene in about 10 vol % can be present in the activator/fillermixture prior to the addition of the first metal catalyst compound.

In another embodiment binders are added to the mix. These can be addedas a means of improving the particle morphology, i.e. narrowing theparticle size distribution, lower porosity of the particles and allowingfor a reduced quantity of alumoxane, which is acting as the ‘binder’.

In another embodiment a solution of a bulky ligand metallocene compoundand optional activator can be combined with a different slurried spraydried catalyst compound and then introduced into a reactor.

The spray dried particles are generally fed into the polymerizationreactor as a mineral oil slurry. Solids concentrations in oil are about10 to 30 weight %, preferably 15 to 25 weight %. In some embodiments,the spray dried particles can be from less than about 10 micrometers insize up to about 100 micrometers, compared to conventional supportedcatalysts which are about 50 micrometers. In a preferred embodiment thesupport has an average particle size of 1 to 50 microns, preferably 10to 40 microns.

F. Catalyst Slurry and Solution Components

The catalyst of the invention can be added to the reaction system in theform of a slurry or a solution or a combination of slurry and solution.In one embodiment, the catalyst in slurry form and includes an activatorand a support, or a supported activator. In another embodiment, thecatalyst slurry includes fumed silica. In another embodiment, the slurryincludes a catalyst compound in addition to the activator and thesupport and/or the supported activator. In one embodiment, the catalystcompound in the slurry is supported.

In another embodiment, the slurry includes one or more activator(s) andsupport(s) and/or supported activator(s) and/or one more catalystcompound(s). For example, the slurry may include two or more activators(such as a supported alumoxane and a modified alumoxane) and a catalystcompound, or the slurry may include a supported activator and more thanone catalyst compounds. Preferably, the slurry comprises a supportedactivator and two catalyst compounds.

In another embodiment the slurry comprises supported activator and twodifferent catalyst compounds, which may be added to the slurryseparately or in combination.

In another embodiment the slurry, containing a supported alumoxane, iscontacted with a catalyst compound, allowed to react, and thereafter theslurry is contacted with another catalyst compound. In anotherembodiment the slurry containing a supported alumoxane is contacted withtwo catalyst compounds at the same time, and allowed to react.

In another embodiment the molar ratio of metal in the activator to metalin the catalyst compound in the slurry is 1000:1 to 0.5:1, preferably300:1 to 1:1, more preferably 150:1 to 1:1.

In another embodiment the slurry contains a support material which maybe any inert particulate carrier material known in the art, including,but not limited to, silica, fumed silica, alumina, clay, talc or othersupport materials such as disclosed above. In a preferred embodiment,the slurry contains a supported activator, such as those disclosedabove, preferably methyl alumoxane and/or modified methyl alumoxane on asupport of silica.

A catalyst slurry can be prepared by suspending the catalyst components,preferably the support, the activator and optional catalyst compounds ina liquid diluent. The liquid diluent is typically an alkane having from3 to 60 carbon atoms, preferably having from 5 to 20 carbon atoms,preferably a branched alkane, or an organic composition such as mineraloil or silicone oil. The diluent employed is preferably liquid under theconditions of polymerization and relatively inert. The concentration ofthe components in the slurry is controlled such that a desired ratio ofcatalyst compound(s) to activator, and/or catalyst compound to catalystcompound is fed into the reactor.

Typically, as a slurry, the catalyst compound and the support andactivator, or supported activator, and the slurry diluent are allowed tocontact each other for a time sufficient for at least 50% of thecatalyst compounds to be deposited into or on the support, preferably atleast 70%, preferably at least 75%, preferably at least 80%, morepreferably at least 90%, preferably at least 95%, preferably at least99%. In an embodiment, the slurry is prepared prior to its use in thecatalyst feed system. Times allowed for mixing are up to 10 hours,typically up to 6 hours, more typically 4 to 6 hours. In one embodimentof this invention a catalyst compound will be considered to be in or onthe support if the concentration of the catalyst compound in the liquidportion of the slurry is reduced over time after adding the catalystcompound to the slurry. Concentration of the catalyst compound in theliquid diluent may be measured for example, by inductively coupledplasma spectroscopy (ICPS), or by ultraviolet (UV) spectroscopy, afterstandardization with a calibration curve prepared at the appropriateconcentration range, as is known in the art. Thus for example, 70% of acatalyst compound will be considered to have deposited in or on asupport if the concentration of the catalyst compound in the liquid (notincluding the support) is reduced by 70% from its initial concentration.

In one embodiment, the catalyst compounds are added to the slurry as asolution, slurry, or powder. The slurry may be prepared prior to its usein the polymerization process of the invention or it may be preparedin-line.

In one embodiment, the slurry is prepared by combining the catalystcomponents, such as for example the catalyst or supported catalyst andthe support and activator or supported activator, all at once. Inanother embodiment, the slurry is prepared by first adding a supportmaterial, then adding the combination of a catalyst and an activatorcomponent.

In another embodiment the slurry comprises a supported activator and atleast one catalyst compound where the catalyst compound is combined withthe slurry as a solution. A preferred solvent is mineral oil.

In a another embodiment, alumoxane, preferably methyl alumoxane ormodified methyl alumoxane, is combined with a support such as calcinedsilica or fumed silica to form a supported activator, the supportedactivator is then dispersed in a liquid, such as degassed mineral oil,and then one or more catalyst compounds are added to the dispersion andmixed to form the catalyst component slurry. The catalyst compounds arepreferably added to the dispersion as a solid, powder, solution or aslurry, preferably a slurry of mineral oil. If more than one catalystcompound is added to the dispersion, the catalyst compounds can be addedsequentially, or at the same time.

In another embodiment the catalyst compound is added to the slurry insolid or powder form. In a preferred embodiment, a Group 15 containingcatalyst compound is added to the slurry in powder or solid form. Inanother preferred embodiment, [(2,4,6-Me₃C₆H₂)NCH₂CH₂]₂NHZrBz₂ and or[(2,4,6-Me₃C₆H₂)NCH₂CH₂]₂NHHfBz₂ is added to the slurry as a powder.

In a preferred embodiment the slurry comprises mineral oil and has aviscosity of about 130 to about 2000 cP at 20° C., more preferably about180 to about 1500 cP at 20° C. and even more preferably about 200 toabout 800 cP at 20° C. as measured with a Brookfield model LVDV-IIIRheometer housed in a nitrogen purged drybox (in such a manner that theatmosphere is substantially free of moisture and oxygen, i.e. less thanseveral ppmv of each). The slurry can be made in a nitrogen purgeddrybox, and rolled in closed glass containers until immediately beforethe viscosity measurements are made, in order to ensure that it is fullysuspended at the start of the trial.

In one embodiment, the slurry comprises a supported activator and one ormore or a combination of the catalyst compound(s) described in Formula Ito IX above.

In another embodiment, the slurry comprises a supported activator andone or more or a combination of the Group 15 catalyst compound(s)represented by Formula I or II described above.

In another embodiment, the slurry comprises a supported activator andone or more or combination of the bulky ligand catalyst compound(s)represented by Formula III to VI described above.

In another embodiment, the slurry comprises supported activator, a Group15 catalyst compound(s) represented by Formula I or II described above,and a the bulky ligand catalyst compound(s) represented by Formula IIIto VI.

In another embodiment, the slurry comprises supported alumoxane and[(2,4,6-Me₃C₆H₂)NCH₂CH₂]₂NH MBz₂ where M is a Group 4 metal, each Bz isa independently a benzyl group and Me is methyl.

In another embodiment, the slurry comprises a supported alumoxane, aGroup 15 catalysts compound and one of the following: bis(n-propylcyclopentadienyl)-MX₂,(pentamethylcyclopentadienyl)(n-propylcyclopentadienyl)MX₂,bis(indenyl)-MX₂, or (tetramethylcyclopentadienyl) (n-propylcyclopentadienyl) MX₂, where M is zirconium, hafnium or titanium and Xis chlorine, bromine, or fluorine.

In one embodiment, the catalyst is added to the reaction system as asolution that includes a catalyst compound. In another embodiment, thesolution also includes an activator in addition to the catalystcompound.

The solution used in the process of this invention is typically preparedby dissolving the catalyst compound and optional activators in a liquidsolvent. The liquid solvent is typically an alkane, such as a C₅ to C₃₀alkane, preferably a C₅ to C₁₀ alkane. Cyclic alkanes such ascyclohexane and aromatic compounds such as toluene may also be used. Inaddition, mineral oil may be used as a solvent. The solution employedshould be liquid under the conditions of polymerization and relativelyinert. In one embodiment, the liquid utilized in the solution isdifferent from the diluent used in the slurry. In another embodiment,the liquid utilized in the solution is the same as the diluent used inthe slurry.

In a preferred embodiment the ratio of metal in the activator to metalin the catalyst compound in the solution is 1000:1 to 0.5:1, preferably300:1 to 1:1, more preferably 150:1 to 1:1.

In a preferred embodiment, the activator and catalyst compound ispresent in the solution at up to about 90 wt %, preferably at up toabout 50 wt %, preferably at up to about 20 wt %, preferably at up toabout 10 wt %, more preferably at up to about 5 wt %, more preferably atless than 1 wt %, more preferably between 100 ppm and 1 wt % based uponthe weight of the solvent and the activator or catalyst compound.

In one embodiment, the solution comprises any one of the catalystcompounds described in Formula I to IX above.

In another embodiment, the solution comprises a Group 15 catalystcompound represented by Formula I or II described above.

In another embodiment, the solution comprises a bulky ligand catalystcompound represented by Formula III to VI described above.

In a preferred embodiment the solution comprises bis(n-propylcyclopentadienyl)-MX₂,(pentamethylcyclopentadienyl)(n-propylcyclopentadienyl)MX₂,bis(indenyl)-MX₂, (tetramethylcyclopentadienyl)(n-propylcyclopentadienyl) MX₂, where M is a Group 4 metal, preferablyzirconium, hafnium or titanium and X is chlorine, bromine, or fluorine.

In the polymerization process of the invention, any catalyst solutionsmay be combined with any catalyst containing slurry. In addition, morethan one catalyst component may be utilized.

Ideally, the fluorocarbon is inert to the polymerization reaction. By“inert to the polymerization reaction” is meant that the fluorocarbondoes not react chemically with the, monomers, catalyst system or thecatalyst system components. (This is not to say that the physicalenvironment provided by an FC's does not influence the polymerizationreactions, in fact, it may do so to some extent, such as affectingactivity rates. However, it is meant to say that the FC's are notpresent as part of the catalyst system.)

VI. Processes

A. General Process Conditions and Reactor Systems

This invention pertains to any prepolymerization and/or polymerizationprocess, and the process is suitably carried out over a wide range oftemperatures and pressures. Such processes include, for example,solution, gas phase, slurry phase, medium pressure and high pressureprocesses or any combination thereof. Particularly preferred is gasphase or slurry phase polymerization of one or more olefins. In aparticularly preferred embodiment, at least one of the olefins isethylene or propylene.

The prepolymerization and/or polymerization process can be carried outin a batch or continuous process. By continuous is meant a system thatoperates (or is intended to operate) without interuption or cessation.For example a continuous process to produce a polymer would be one inwhich the reactants are continuously introduced into one or morereactors and polymer product is continually withdrawn. In a preferredembodiment any of the polymerization process described herein are acontinuous process.

Polymerization processes according to this invention are carried out atany temperature or temperature range effective in carrying out thepolymerization process. In general, effective temperatures range fromabout −80° C. to 350° C., preferably from about 0° C. to 200° C., morepreferably from about 50° C. to 120° C. In another embodiment, thepolymerization temperature is above room temperature (23° C.),preferably above 30° C., preferably above 50° C., preferably above 70°C.

Polymerization processes according to this invention are carried out atany pressure or pressure range effective in carrying out thepolymerization process. The pressures employed may be in the range from1 mm Hg (133 Pa) to about 3500 bar (350 MPa), preferably from 0.5 bar(50 kPa) to about 500 bar (50 MPa), more preferably from about 1 bar(100 kPa) to about 100 bar (10 MPa), and most preferably from about 5bar to about 50 bar (5 MPa).

In one embodiment, the process of this invention is directed toward asolution, medium pressure, high pressure, slurry phase or gas phasepolymerization process of one or more olefin monomers having from 2 to30 carbon atoms, preferably 2 to 12 carbon atoms, and more preferably 2to 8 carbon atoms. The invention is particularly well suited to thepolymerization of one or more olefin monomers of ethylene, propylene,1-butene, 1-pentene, 4-methyl-pentene-1,1-hexene, 1-octene and 1-decene.

In another preferred embodiment of the invention, ethylene ispolymerized with a comonomer, the comonomer having at least onealpha-olefin having from 3 to 15 carbon atoms, preferably from 4 to 12carbon atoms, and most preferably from 4 to 8 carbon atoms. Preferablythe reaction is carried out in a gas phase process.

In another embodiment of the invention, ethylene or propylene ispolymerized with at least two different comonomers, optionally one ofwhich may be a diene, to form a terpolymer.

In yet another embodiment, the mole ratio of comonomer to ethylene,C_(x)/C₂, where C_(x) is the amount of comonomer and C₂ is the amount ofethylene, is from about 0.001 to 0.4 and more preferably from about 0.02to 0.2.

In one embodiment, the invention is directed to a polymerizationprocess, particularly a gas phase or slurry phase process, forpolymerizing propylene alone or with one or more other monomersincluding ethylene, and/or other olefins having from 4 to 12 carbonatoms. Polypropylene polymers may be produced using the particularlybridged bulky ligand metallocene catalysts as described in U.S. Pat.Nos. 5,296,434 and 5,278,264, both of which are herein incorporated byreference.

Another preferred process of the invention is where the process,preferably a slurry or gas phase process is operated in the presence ofa bulky ligand metallocene catalyst system of the invention and in theabsence of or essentially free of any scavengers, such astriethylaluminum, trimethylaluminum, tri-isobutylaluminum andtri-n-hexylaluminum and diethyl aluminum chloride, dibutyl zinc and thelike. This preferred process is described in PCT publication WO 96/08520and U.S. Pat. Nos. 5,712,352 and 5,763,543, which are herein fullyincorporated by reference.

In one embodiment of the invention, olefin(s), preferably C₂ to C₃₀olefin(s) or alpha-olefin(s), preferably ethylene or propylene orcombinations thereof are prepolymerized in the presence of themetallocene catalyst systems of the invention described above prior tothe main polymerization. In one embodiment, the prepolymerizationprocess is carried out in a gas, solution or slurry phase at effectiveprepolymerization temperatures and pressures. The prepolymerization cantake place with any olefin monomer or combination and/or in the presenceof any molecular weight controlling agent such as hydrogen. For examplesof prepolymerization procedures, see U.S. Pat. Nos. 4,748,221,4,789,359, 4,923,833, 4,921,825, 5,283,278 and 5,705,578 and Europeanpublication EP-B-0279 863 and PCT Publication WO 97/44371 all of whichare herein fully incorporated by reference.

In one embodiment, the polymerization is carried out where the catalyst,monomer, and diluent are present in a single phase. In a preferredembodiment, polymerization is carried out as a continuous polymerizationprocess in which catalyst, monomer, and diluent are present in a singlephase. By continuous is meant a system that operates (or is intended tooperate) without interuption or cessation. For example a continuousprocess to produce a polymer would be one where the reactants arecontinuously introduced into one or more reactors and polymer product iscontinually withdrawn.

The reactor used in the polymerization process of this invention, willcontain sufficient amounts of the catalyst system effective to catalyzethe polymerization of the monomer containing feed-stream such that asufficient amount of polymer having desired characteristics is produced.The feed stream in one embodiment contains a total monomer concentrationgreater than 5 wt % (based on the total weight of the monomers, diluent,and catalyst system), preferably greater than 15 wt %, greater than 30wt % in another embodiment. In yet another embodiment, the feed-streamwill contain from 5 wt % to 50 wt % monomer concentration based on thetotal weight of monomer, diluent, and catalyst system.

In one embodiment of the invention, hydrogen is added to the reactor formolecular weight control. As is well known to those skilled in the art,increased concentrations of hydrogen relative to the concentration ofmonomer(s) in the reactor cause the production of polymer of lowernumber average and weight average molecular weights.

In one embodiment of the invention, a liquid process is employed, whichcomprises contacting olefin monomers with polymerization catalyst in anoptional solvent and allowing the monomers to react for a sufficienttime to produce the desired polymers. Hydrocarbon solvents suitable forthe process include aliphatic and aromatic solvents. Alkanes, such ashexane, pentane, isopentane, and octane, are preferred.

B. Gas Phase Embodiments

One embodiment of the invention incorporates the use of a gas phasepolymerization process. Typically in a gas phase polymerization processa continuous cycle is employed where in one part of the cycle of areactor system, a cycling gas stream, otherwise known as a recyclestream or fluidizing medium, is heated in the reactor by the heat ofpolymerization. This heat is removed from the recycle composition inanother part of the cycle by a cooling system external to the reactor.Generally, in a gas fluidized bed process for producing polymers, agaseous stream containing one or more monomers is continuously cycledthrough a fluidized bed in the presence of a catalyst under reactiveconditions. The gaseous stream is withdrawn from the fluidized bed andrecycled back into the reactor. Simultaneously, polymer product iswithdrawn from the reactor and fresh monomer is added to replace thepolymerized monomer. See, for example, U.S. Pat. Nos. 4,543,399,4,588,790, 5,028,670, 5,317,036, 5,352,749, 5,405,922, 5,436,304,5,453,471, 5,462,999, 5,616,661 and 5,668,228, all of which are fullyincorporated herein by reference.

The reactor pressure in a gas phase process may vary from about 100 psig(690 kPa) to about 600 psig (4138 kPa), preferably in the range of fromabout 200 psig (1379 kPa) to about 400 psig (2759 kPa), more preferablyin the range of from about 250 psig (1724 kPa) to about 350 psig (2414kPa).

The productivity of the catalyst or catalyst system in a gas phasesystem is influenced by the partial pressure of the main monomer. Thepreferred mole percent of the main monomer, ethylene or propylene, isfrom about 25 to 90 mole percent and the comonomer partial pressure isin the range of from about 138 kPa to about 517 kPa, preferably about517 kPa to about 2069 kPa, which are typical conditions in a gas phasepolymerization process. Also in some systems the presence of comonomercan increase productivity.

The reactor temperature in a gas phase process may vary from about 30°C. to about 120° C., preferably from about 60° C. to about 115° C., morepreferably in the range of from about 70° C. to 110° C., and mostpreferably in the range of from about 70° C. to about 95° C.

Other gas phase processes contemplated by the process of the inventioninclude series or multistage polymerization processes. Also gas phaseprocesses contemplated by the invention include those described in U.S.Pat. Nos. 5,627,242, 5,665,818 and 5,677,375, and European publicationsEP-A-0 794 200 EP-B1-0 649 992, EP-A-0 802 202 and EP-B-634 421 all ofwhich are herein fully incorporated by reference.

In a preferred embodiment, the reactor and processes utilized in theinvention are capable of producing greater than 500 lbs of polymer perhour (227 kg/hr) to about 200,000 lbs/hr (90,900 kg/hr) or higher ofpolymer, preferably greater than 1000 lbs/hr (455 kg/hr), morepreferably greater than 10,000 lbs/hr (4540 kg/hr), even more preferablygreater than 25,000 lbs/hr (11,300 kg/hr), still more preferably greaterthan 35,000 lbs/br (15,900 kg/hr), still even more preferably greaterthan 50,000 lbs/hr (22,700 kg/hr) and most preferably greater than65,000 lbs/hr (29,000 kg/hr) to greater than 100,000 lbs/hr (45,500kg/hr).

In another preferred embodiment the catalyst system in is liquid formand is introduced into the gas phase reactor into a resin particle leanzone. For information on how to introduce a liquid catalyst system intoa fluidized bed polymerization into a particle lean zone, please seeU.S. Pat. No. 5,693,727, which is incorporated by reference herein.

C. Slurry Process Embodiments

One embodiment of the invention incorporates the use of a slurry phasepolymerization process, preferably as a continuous polymerizationprocess. The slurry polymerization process is preferably carried out atpressures in the range of from about 1 to about 100 atmospheres,preferably in the range of from 1 to 50 atmospheres. Operatingtemperatures are generally in the range of 0° C. to about 120° C.

In one embodiment of the slurry process, the monomers, catalyst(s), andinitiator(s) are miscible in the diluent or diluent mixture, i.e.,constitute a single phase, while the polymer precipitates from thediluent with good separation from the diluent. In one embodiment, asolvent or co-diluent is added to the reaction process. In a particularembodiment, an alkane having from 3 to 7 carbon atoms, preferably abranched alkane, is added. Preferred alkanes include isobutane andisohexane.

A preferred polymerization technique of the invention is referred to asa particle form polymerization, which is essentially a slurry processutilizing a supported catalyst wherein the temperature is kept below thetemperature at which the polymer goes into solution. Such technique iswell known in the art, and described in for instance U.S. Pat. No.3,248,179, which is fully incorporated herein by reference. Other slurryprocesses include those employing a loop reactor and those utilizing aplurality of stirred reactors in series, parallel, or combinationsthereof. Non-limiting examples of slurry processes include continuousloop or stirred tank processes. Also, other examples of slurry processesare described in U.S. Pat. Nos. 4,613,484 and 5,986,021, which areherein fully incorporated by reference.

In one embodiment, the reactor used in the slurry process of theinvention is capable of producing greater than 500 lbs of polymer perhour (227 kg/hr) to about 200,000 lbs/hr (90,900 kg/hr) or higher ofpolymer, preferably greater than 1000 lbs/hr (455 kg/hr), morepreferably greater than 10,000 lbs/hr (4540 kg/hr), even more preferablygreater than 25,000 lbs/hr (11,300 kg/hr), still more preferably greaterthan 35,000 lbs/hr (15,900 kg/hr), still even more preferably greaterthan 50,000 lbs/hr (22,700 kg/hr) and most preferably greater than65,000 lbs/hr (29,000 kg/hr) to greater than 100,000 lbs/hr (45,500kg/hr).

In one embodiment, polymer granules and supported catalyst particles arepresent as solid particles in the slurry reactor, and the slurry diluentis a hydrofluorocarbon, one or more hydrocarbons, or mixtures thereof.In one embodiment, the concentration of solid particles in the slurry isequal to or greater than 10 vol %. In another embodiment, the solidparticles are present in the slurry at a concentration equal to orgreater than 25 vol %. In yet another embodiment, the solid particlesare present in the slurry at a concentration less than or equal to 75vol %. In yet another embodiment, the solid particles are present in theslurry at concentrations ranging from 1 to 70 vol %; from 5 to 70 vol %;from 10 to 70 vol %; from 15 to 70 vol %; from 20 to 70 vol %; from 25to 70 vol %; from 30 to 70 vol %; or from 40 to 70 vol %.

D. Solution Process

In one embodiment, the process of this invention is carried out as asolution polymerization process. Generally, the solution processinvolves polymerization in a continuous reactor in which the startingmonomer(s) and catalyst materials supplied and the polymer formed, areagitated to reduce or avoid concentration gradients. Suitable processesoperate above the melting point of the polymers at high pressures, from1 bar (100 kPa) to 3000 bar (300 MPa), in which the monomer acts asdiluent or in solution polymerization using a solvent.

Temperature control in the reactor is obtained by balancing the heat ofpolymerization and with reactor cooling by reactor jackets or coolingcoils to cool the contents of the reactor, auto refrigeration,pre-chilled feeds, vaporization of liquid medium (diluent, monomers orsolvent) or combinations of all three. Adiabatic reactors withpre-chilled feeds may also be used. The reactor temperature depends onthe catalyst used. In general, the reactor temperature preferably canvary between about 0° C. and about 160° C., more preferably from about10° C. to about 140° C., and most preferably from about 40° C. to about120° C. In series operation, the second reactor temperature ispreferably higher than the first reactor temperature. In parallelreactor operation, the temperatures of the two reactors are independent.The pressure can vary from about 1 mm Hg (133 Pa) to 2500 bar (250 MPa),preferably from 0.1 bar (10 kPa) to 1600 bar (160 MPa), most preferablyfrom 1.0 (100 kPa) to 500 bar (50 MPa).

Examples of solution processes are described in U.S. Pat. Nos.4,271,060, 5,001,205, 5,236,998, 5,589,555 and 5,977,251 and PCT WO99/32525 and PCT WO 99/40130, which are fully incorporated herein byreference.

E. Medium and High Pressure Polymerization

The polymerization process of this invention can also be carried out atmedium or high pressures. For medium pressure processes, the temperatureat which the polymerization reaction occurs is at least 80° C. andranges from 80° C. to 250° C., preferably from 100° C. to 220° C., andshould for a given polymer in the reactor, be above the melting point ofsaid polymer so as to maintain the fluidity of the polymer-rich phase.The pressure can be varied from 100 to 1000 bar for ethylenehomopolymers and from 30 bar (3 MPa) to 1000 bar (100 MPa), especially50 bar (5 MPa) to 500 bar (50 MPa) for processes producing ethylenecopolymers containing C₃ to C₁₀ olefins and optionally othercopolymerizable olefins.

In high pressure processes, particularly for the polymerization ofethylene alone or in combination with C₃ to C₁₀ alpha-olefins, andoptionally other copolymerizable olefins, the temperature of the mediumin which the polymerization reaction occurs is at least 120° C. andpreferably above 140° C. and may range to 350° C., but below thedecomposition temperature of the polymer product, typically from 310° C.to 325° C. Preferably, the polymerization is completed at a temperaturewithin the range of 130° C. to 230° C. The polymerization is completedat a pressure above 200 bar (20 MPa), and generally at a pressure withinthe range of 500 bar (50 MPa) to 3500 bar (350 MPa). Preferably, thepolymerization is completed at a pressure within the range from 800 bar(80 MPa) to 2500 bar (250 MPa).

More recently, polymerization conditions for high pressure and ortemperature polymerizations to prepare propylene homopolymers andcopolymers of propylene with C₃ to C₁₀ olefins and optionally othercopolymerizable olefins have been reported. See U.S. patent application60/431,185 filed Dec. 5, 2002; 60/431,077, filed Dec. 5, 2002; and60/412,541, filed Sep. 20, 2002.

F. Reactors and Reactor Systems

The invention may be practiced in any type of polymerization reactorsystem, such as continuous and batch reaction systems suitable forcarrying out any one or more of the solution, gas phase, slurry phase,medium pressure or high pressure processes. In one embodiment, theinvention is practiced in a fluidized bed reactor, loop reactor, plugflow reactor and/or stirred tank reactor. In a particular embodiment,this invention is practiced in a “butyl reactor.” Other examples ofreactors include any reactor selected from the group consisting of acontinuous flow reactor, stirred tank reactor, plug flow reactor, movingbelt reactor, drum reactor, jet reactor, nozzle reactor, tubularreactor, autorefrigerated boiling-pool reactor or any combinationthereof.

In another aspect, heat can be removed from the reactor system by use ofheat transfer surfaces, such as in a tubular reactor where a coolant ison one side of the tube and the polymerizing mixture is on the otherside. Heat may also be removed by evaporating the polymerizing mixture,such as may be found in an autorefrigerated boiling pool type reactor.Another example, is a plug flow reactor where a portion of thepolymerizing mixture is evaporated as the mixture proceeds through thereactor. Another example is where heat is removed in a plug flow reactorthrough surface heat transfer using coolant on the other side of a heattransfer surface. Another example would be a reactor wherepolymerization takes place on a moving belt or drum where thediluent/monomer/catalyst mixture is sprayed onto the belt or drum andheat is removed by evaporation of the diluent as the reaction proceeds.In addition heat may be removed in such reactors by surface heattransfer (such as where the coolant is present on the inside of the drumor under the belt and the polymer is produced on the other side of thebelt or drum). Another type of reactor is a jet or nozzle reactor. Thesereactors have a short residence time where the monomer, diluent andcatalyst system are combined in the jet or nozzle and the polymerizationoccurs as the mixture passes through the nozzle at high velocity.

One or more reactors in series or in parallel may be used in thisinvention. Catalyst component(s) (and any activator employed) may bedelivered as a solution or slurry, either separately to the reactor,activated in-line just prior to the reactor, or preactivated and pumpedas an activated solution or slurry to the reactor. A preferred operationis two solutions activated in-line. For information on methods tointroduce multiple catalysts into reactors, see U.S. Pat. No. 6,399,722and WO 01/30861 A1. While these reference may emphasize gas phasereactors, the techniques described are equally applicable to other typesof reactors, including continuous stirred tank reactors, slurry loopreactors and the like. Polymerizations are carried out in either singlereactor operation, in which monomer, comonomers, catalyst/activator,scavenger, and optional modifiers are added continuously to a singlereactor or in series reactor operation, in which the above componentsare added to each of two or more reactors connected in series. Thecatalyst component may also be added to both reactors, with onecomponent being added to a first reactor and other components added toother reactors.

In one embodiment, a continuous flow stirred tank-type reactor is used.The reactor is generally fitted with an efficient agitation means, suchas a turbo-mixer or impeller(s), an external cooling jacket and/orinternal cooling tubes and/or coils, or other means of removing the heatof polymerization to maintain the desired reaction temperature, inletmeans (such as inlet pipes) for monomers, diluents and catalysts(combined or separately), temperature sensing means, and an effluentoverflow or outflow pipe which withdraws polymer, diluent and unreactedmonomers among other things, to a holding drum or quench tank.Preferably, the reactor is purged of air and moisture. One skilled inthe art will recognize proper assembly and operation. The reactors arepreferably designed to deliver good mixing of the catalyst and monomerswithin the reactor, good turbulence across or within the heat transfertubes or coils, and enough fluid flow throughout the reaction volume toavoid excessive polymer accumulation or separation from the diluent.

In another embodiment of the invention, a reactor capable of performinga continuous slurry process, such as disclosed in U.S. Pat. No.5,417,930, herein incorporated by reference, is used. A reactor pumpimpeller is employed in the reactor and can be of the up-pumping varietyor the down-pumping variety.

The order of contacting the monomer feed-stream, catalyst, initiator,and diluent may be variable. In one embodiment, the initiator andcatalyst are pre-complexed by mixing together in the selected diluentfor a prescribed amount of time ranging from 0.01 second to 10 hours,and then is injected into a continuous reactor through a catalyst nozzleor injection apparatus. In yet another embodiment, catalyst and theinitiator are added to the reactor separately. In another embodiment,the initiator is blended with the feed monomers before injection to thereactor. Desirably, the monomer is not contacted with the catalyst, orthe catalyst combined with the initiator before entering the reactor.

VII. Polymer Products

Polymers produced according to this invention are olefin polymers or“polyolefins”. By olefin polymers is meant that at least 75 mole % ofthe polymer is made of hydrocarbon monomers, preferably at least 80 mole%, preferably at least 85 mole %, preferably at least 90 mole %,preferably at least 95 mole %, preferably at least 99 mole %. In aparticularly preferred embodiment, the polymers are 100 mole %hydrocarbon monomer. Hydrocarbon monomers are monomers made up of onlycarbon and hydrogen. In another embodiment of the invention up to 25 mol% of the polyolefin is derived from heteroatom containing monomers.Heteroatom containing monomers are hydrocarbon monomers where one ormore hydrogen atoms have been replaced by a heteroatom. In a preferredembodiment, the heteroatom is selected from the group consisting ofchlorine, bromine, oxygen, nitrogen, silicon and sulfur, preferably theheteroatom is selected from the group consisting of oxygen, nitrogen,silicon and sulfur, preferably the heteroatom is selected from the groupconsisting of oxygen and nitrogen, preferably oxygen. In a preferredembodiment, the heteroatom is not fluorine. In another embodiment of theinvention, the monomers to be polymerized are not fluormonomers.Fluoromonomers are defined to be hydrocarbon monomers where at least onehydrogen atom has been replaced by a fluorine atom. In anotherembodiment of the invention, the monomers to be polymerized are nothalomonomers. (By halomonomer is meant a hydrocarbon monomer where atleast one hydrogen atom is replaced by a halogen.) In another embodimentof the invention, the monomers to be polymerized are not vinyl aromatichydrocarbons. In another embodiment of the invention, the monomers to bepolymerized are preferably aliphatic or alicyclic hydrocarbons. (asdefined under “Hydrocarbon” in Hawley's Condensed Chemical Dictionary,13th edition, R. J. Lewis ed., John Wiley and Sons, New York, 1997. Inanother embodiment of the invention, the monomers to be polymerized arepreferably linear or branched alpha-olefins, preferably C2 to C40 linearor branched alpha-olefins, preferably C2 to C20 linear or branchedalpha-olefins, preferably ethylene, propylene, butene, pentene, hexene,heptene, octene, nonene, decene, undecene, dodecene, or mixturesthereof, more preferably ethylene, propylene, butene hexene and octene.

A. General Polymer Products

The polymers produced by the process of the invention can be used in awide variety of products and end-use applications. The polymers producedby the process of the invention include linear low density polyethylene,elastomers, plastomers, high density polyethylenes, medium densitypolyethylenes, low density polyethylenes, multimodal or bimodal highmolecular weight polyethylenes, polypropylene and polypropylenecopolymers.

B. Density

The polymers produced according to this invention can be produced at anydensity suitable for the appropriate end use. In one embodiment, therecan be produced ethylene based polymers having a density in the range offrom 0.86 g/cc to 0.97 g/cc. For some applications, a density in therange of from 0.88 g/cc to 0.920 g/cc is preferred while in otherapplications, such as pipe, film and blow molding, a density in therange of from 0.930 g/cc to 0.965 g/cc is preferred. For low densitypolymers, such as for film applications, a density of 0.910 g/cc to0.940 g/cc is preferred. Density is measured in accordance with ASTMmethod 1505.

C. Molecular Weight and Molecular Weight Distribution

The polymers produced by the process of the invention can be produced ina wide variety of molecular weights and molecular weight distributions.Molecular weights (weight average molecular weight (Mw) and numberaverage molecular weight (Mn)) are preferably determined using a Waters150 Size Exclusion Chromatograph (SEC) equipped with a differentialrefractive index detector (DRI), an online low angle light scattering(LALLS) detector and a viscometer (VIS). The details of the detectorcalibrations are described by T. Sun, P. Brant, R. R. Chance, and W. W.Graessley, Macromolecules, Volume 34, Number 19, 6812-6820, (2001), andare incorporated herein by reference.

In an embodiment of the invention, the polymers produced have amolecular weight distribution (MWD), which is defined as a ratio ofweight average molecular weight to number average molecular weight(MWD=M_(w)/M_(n)), of greater than 1.5, preferably from 1.5 to about 70.In some embodiments, the polymer has a M_(w)/M_(n) of at least 2,preferably from about 2 to 60, while in other embodiments the polymerproduced has a M_(w)/M_(n) of at least 5, preferably from about 5 to 50.In an embodiment, the polymer of the invention has a narrow molecularweight distribution and a broad composition distribution, andvice-versa, such as those polymers described in U.S. Pat. No. 5,798,427,incorporated herein by reference.

In another embodiment, the polyolefin produced has at least two speciesof molecular weights. Preferably, both species are present at greaterthan 20 wt %, based upon weight average molecular weight.

D. Bi- or Multi-Modal Polymers

In another embodiment of this invention, the polymer produced is bi- ormulti-modal (on the SEC graph). By bi- or multi-modal means that the SECgraph of the polymer has two or more positive slopes, two or morenegative slopes, and three or more inflection points (an inflectionpoint is that point where the second derivative of the curve is equal tozero) or the graph has at least has one positive slope, one negativeslope, one inflection point and a change in the positive and or negativeslope greater than 20% of the slope before the change.

In one embodiment, the SEC graph has one positive slope, one negativeslope, one inflection point and an Mw/Mn of 10 or more, preferably 15 ormore, more preferably 20 or more. The columns are calibrated by runninga series of narrow polystyrene standards and the molecular weights werecalculated using Mark Houwink coefficients for the polymer in question.

In a particular embodiment, bi-modal polymers are produced having adensity of 0.93 to 0.96 g/cc, an MI (I₂) of 0.03-0.10 g/10 min, an FI(I₂₁) of 4-12 g/10 min, an MFR (I₂₁/I₂) of 80-180, an overall Mw of200,000 to 400,000, an overall Mn of 5,000-10,000 and an Mw/Mn of 20-50.Preferably, the particular polymers have a low molecular weight fraction(˜500-˜50,000) having a density of 0.935-0.975 g/cc and a high molecularweight fraction (˜50,000-˜8,000,000) having a density of 0.910-0.950g/cc. These polymers are particularly useful for film and pipe,especially, for PE-100 pipe applications. The molecular weightdistributions (MWDs), as obtained from size exclusion chromatography(SEC), can be deconvoluted using a bimodal fitting program. In oneembodiment, the polymer has weight ratio of the high molecular weight(HMW) fraction to the low molecular weight (LMW) fraction of rangingfrom 20-80 to 80-20, more preferably from 30-70 to 70-30, and even morepreferably from 40-60 to 60-40. A higher wt % of HMW than LMW wt % ispreferred. The SEC curve can be further analyzed to give percent of wt%>1 MM, which is the weight percent of the total MWD that has amolecular weight greater than 1 million, and wt %>100K, which is theweight percent of the total MWD that is greater than 100,000 inmolecular weight. The weight percent ratio is simply wt %>1 MM dividedby wt %>100K. 100,000 was used as an approximate means of dividing thetotal MWD into a HMW (high molecular weight) and LMW (low molecularweight) region. This ratio gives a simple but sensitive indication ofthe relative amount of the very high molecular weight species in the HMWregion of the MWD. The preferred embodiment of the polymer has thepreferred range of weight percent ratio (WPR), higher than 10 but lessthan 30, preferably higher than 15 but less than 25.

In another embodiment, a bimodal molecular weight polymer is producedhaving a density of 0.93 to 0.97 g/cc, an MI (i₁₂) of 0.02-0.5 g/10 min,an FI (I₂₁) of 10-40 g/10 min, an MFR (I₂₁/I₂) of 50-300, an Mw of100,000 to 500,000, an Mn of 8,000-20,000 and an Mw/Mn of 10-40. Thesepolymers are particularly useful for blow molding applications. Thesebimodal polymers exhibit high Bent Strip ESCR (environmental stresscrack resistance) performance, which far exceeds the performance ofunimodal HDPE. Also, the blow molded bottles trim easier and typicallyhave an opaque finish, which is preferred over a translucent finish ofunimodal HDPE.

E. Composition Distribution Breadth Index

The polymers of the invention may have a narrow or broad compositiondistribution as measured by Composition Distribution Breadth Index(CDBI). Further details of determining the CDBI of a copolymer are knownto those skilled in the art. See, for example, PCT Patent Application WO93/03093, published Feb. 18, 1993, which is fully incorporated herein byreference. In some embodiments the polymer produced may have a CDBI of80% or more or may have a CDBI of 50% or less.

In one embodiment, the polymers of the invention have CDBI's generallyin the range of greater than 50% to 100%, preferably 99%, preferably inthe range of 55% to 85%, and more preferably 60% to 80%, even morepreferably greater than 60%, still even more preferably greater than65%. In another embodiment, polymers produced using this invention havea CDBI less than 50%, more preferably less than 40%, and most preferablyless than 30%.

F. Melt Index

The polymers produced by the process of the invention can be producedaccording to a desired or predetermined melt index, depending upondesired end use. In one embodiment, the polymers have a melt index (MI)or (I₂), as measured by ASTM-D-1238-E, in the range from 0.01 dg/min to1000 dg/min, more preferably from about 0.01 dg/min to about 100 dg/min,even more preferably from about 0.01 dg/min to about 50 dg/min, and mostpreferably from about 0.1 dg/min to about 10 dg/min.

In another embodiment of the invention, the polymers have a melt indexratio (I₂₁/I₂) (I₂₁ is measured by ASTM-D-1238-F) of from 10 to lessthan 25, more preferably from about 15 to less than 25.

The polymers of the invention in a preferred embodiment have a meltindex ratio of from preferably greater than 25, more preferably greaterthan 30, even more preferably greater that 40, still even morepreferably greater than 50 and most preferably greater than 65. Inanother embodiment, the polymer of the invention has a narrow molecularweight distribution and a broad composition distribution or vice-versa.Examples include those polymers described in U.S. Pat. No. 5,798,427,the description of which is incorporated herein by reference.

G. Tacticity

The term “tacticity” refers to the stereochemical configuration of apolymer, and the properties of a polymer having side chains are affectedby its tacticity. For example, adjacent monomer units having side chainscan have either like or opposite configuration. If all monomer unitshave like configuration, the polymer is “isotactic.” If adjacent monomerunits have an alternating configuration, and this alternatingconfiguration continues along the entire polymer chain, the polymer is“syndiotactic.” If the configuration of monomer units is random, thepolymer is “atactic.” When two contiguous monomer units, a “diad,” havethe same configuration, the diad is called isotactic or “meso” (m). Whenthe monomer units have opposite configuration, the diad is called“racemic” (r). For three adjacent monomer units, a “triad,” there arethree possibilities. If the three adjacent monomer units have the sameconfiguration, the triad is designated mm. An rr triad has the middlemonomer unit having an opposite configuration from either neighbor. Iftwo adjacent monomer units have the same configuration and it isdifferent from the third monomer, the triad is designated as having mrtacticity. For five contiguous monomer units, a “pentad,” there are tenpossibilities: mmmm, mmmr, rmmr, mmrr, mrmm, rmrr, mrmr, rrrrr, rrrr,and mrrm. A completely syndiotactic polymer would have all rrrr pentads,while a completely isotactic polymer would have all mmmm pentads. Theconfiguration can be determined by ¹³C nuclear magnetic resonancespectroscopy as described in Macromolecules 8 687 (1975) and inMacromolecules 6 925 (1973) and references cited therein. For moreinformation on polymer stereochemistry, see G. Odian, Principles ofPolymerization, 2nd edition, pages 568-580 (1981).

Propylene based polymers can be produced using the process of thisinvention at various levels of tacticity. Examples of such polymersinclude atactic polypropylene, isotactic polypropylene, hemi-isotacticand syndiotactic polypropylene or mixtures thereof produced by using twoor more different catalysts in the practice of this invention. Otherpropylene polymers include propylene block or impact copolymers.Propylene polymers of these types are well known in the art, see forexample U.S. Pat. Nos. 4,794,096, 3,248,455, 4,376,851, 5,036,034 and5,459,117, all of which are herein incorporated by reference.

In one embodiment of the invention, the polymer is polypropylene that ishighly isotactic, readily forms a crystalline structure and hasexcellent chemical and heat resistance. In another embodiment, thepolypropylene made by the process of the invention is highlysyndiotactic. In yet another embodiment, the polypropylene made by theprocess of the invention is characterized in that it has low levels ofisotacticity and/or low levels of syndiotacticity. In a particularembodiment, the percent of pentads having mmmm configuration is lessthan 40%, preferably more than 2%, and more preferably less than 30%. Inyet another particular embodiment, the percent of pentads having rrrr isless than 75%, preferably more than 5% and more preferably less than50%. At lower levels of syndiotacticity and isotacticity, the polymer ispredominantly or even completely amorphous, generally has no meltingpoint, is generally transparent and flexible, and has good elasticproperties.

H. Polymer Blends

The polymers of the invention may be blended and/or coextruded with anyother polymer. Non-limiting examples of other polymers include linearlow density polyethylenes produced via conventional Ziegler-Natta and/orbulky ligand metallocene catalysis, elastomers, plastomers, highpressure low density polyethylene, high density polyethylenes,polypropylenes and the like.

I. Appearance

The films produced using the polymers of this invention have goodappearance properties. In one embodiment, the films have a low gelcontent and/or have good haze and gloss. In a preferred embodiment, a 1mil (1.0 mil=0.25 μm) film is produced that has a 45° gloss of 7 ormore, preferably 8 or more, as measured by ASTM D 2475. In a preferredembodiment the 1 mil film (1.0 mil=25 μm) has a haze of 75 of less,preferably 70 or less as measured by ASTM D 1003, condition A.

J. Articles

Polymers produced by the process of the invention and blends thereof areuseful in producing any variety of articles. For example, the polymersare useful in such forming operations as film, sheet, and fiberextrusion and co-extrusion as well as blow molding, injection moldingand rotary molding. Films include blown or cast films formed bycoextrusion or by lamination useful as shrink film, cling film, stretchfilm, sealing films, oriented films, snack packaging, heavy duty bags,grocery sacks, baked and frozen food packaging, medical packaging,industrial liners, membranes, etc. in food-contact and non-food contactapplications. Fibers include melt spinning, solution spinning and meltblown fiber operations for use in woven or non-woven form to makefilters, diaper fabrics, medical garments, geotextiles, etc. Extrudedarticles include medical tubing, wire and cable coatings, pipe,geomembranes, and pond liners. Molded articles include single andmulti-layered constructions in the form of bottles, tanks, large hollowarticles, rigid food containers and toys, etc.

The films may be formed by any of the conventional techniques known inthe art including extrusion, co-extrusion, lamination, blowing andcasting. The film may be obtained by the flat film or tubular processwhich may be followed by orientation in a uniaxial direction or in twomutually perpendicular directions in the plane of the film to the sameor different extents. Orientation may be to the same extent in bothdirections or may be to different extents. Particularly preferredmethods to form the polymers into films include extrusion or coextrusionon a blown or cast film line.

In another embodiment, the polymer of the invention is made into a filmby methods known in the art. For film applications, the polymers of theinvention have an I₂₁ value of from about 2 to about 100 dg/min,preferably from about 2 to about 50 dg/min, and more preferably fromabout 2 to about 30 dg/min. I₂₁ is measured by ASTM Method D 1238.

In another embodiment, the polymer of the invention is made into amolded article by methods known in the art, for example, by blow moldingand injection-stretch molding. For molded applications, the polymers ofthe invention have a I₂₁ of from about 20 dg/min to about 50 dg/min andpreferably from about 35 dg/min to about 45 dg/min.

In another embodiment, the polymer of the invention is made into a pipeby methods known in the art. For pipe applications, the polymers of theinvention have a I₂₁ of from about 2 to about 10 dg/min and preferablyfrom about 2 to about 8 dg/min. In another embodiment, the pipe of theinvention satisfies ISO qualifications. In another embodiment, thepresent invention is used to make polyethylene pipe having a predictedS-4 T_(c) for 110 mm pipe of less than −5° C., preferably of less than−15° C. and more preferably less than −40° C. (ISO DIS 13477/ASTMF1589).

In another embodiment, the polymer has an extrusion rate of greater thanabout 17 lbs/hour/inch of die circumference and preferably greater thanabout 20 lbs/hour/inch of die circumference and more preferably greaterthan about 22 lbs/hour/inch of die circumference.

The objects produced (such as films, pipes, etc) may further containadditives such as slip, antiblock, antioxidants, pigments, fillers,antifog, UV stabilizers, antistats, polymer processing aids,neutralizers, lubricants, surfactants, pigments, dyes and nucleatingagents. Preferred additives include silicon dioxide, synthetic silica,titanium dioxide, polydimethylsiloxane, calcium carbonate, metalstearates, calcium stearate, zinc stearate, talc, BaSO₄, diatomaceousearth, wax, carbon black, flame retarding additives, low molecularweight resins, hydrocarbon resins, glass beads and the like. Theadditives may be present in the typically effective amounts well knownin the art, such as 0.001 weight % to 10 weight %.

The polymers of the invention may be blended and/or coextruded with anyother polymer. Non-limiting examples of other polymers include linearlow density polyethylenes produced via conventional Ziegler-Natta and/orbulky ligand metallocene catalysis, elastomers, plastomers, highpressure low density polyethylene, high density polyethylenes,polypropylenes and the like.

VIII. Product Recovery

Polymer product that leaves the reactor unit of the reaction systemcontains entrained and or dissolved material that should be separatedfrom the polymer. (For ease of reference whenever entrained materialsare referred to, the term also includes dissolved materials.) Includedin this polymer product are unreacted monomers and undesirablehydrocarbon by-products of the reaction process. Also included are anydiluent and/or solvent materials that are not reactive to form desirablepolymer, and may be especially problematic with regard to removal and/orrecovery.

A substantial portion (i.e., a majority) of the polymer product isseparated from the non-polymer product by sending product effluent fromthe polymer reactor to a polymer recovery system. The polymer recoverysystem is operated by controlling a variety of parameters includingtemperature, pressure, vapor-liquid separation systems, and purgesystems or vessels.

In one embodiment, the polymer recovery system incorporates the use ofan inert gas to purge or scrub out undesirable entrained material fromthe polymer product. The inert gas is a composition that issubstantially non-reactive with the polymer product, and can be used insufficient quantity as a driving force to separate the non-polymercomponents from the polymer product. Examples of useful inert gasesinclude air, nitrogen, water vapor, methane, ethane, and carbon dioxide.

In a particular embodiment, polymer associated with entrained materialssuch as unreacted monomer, hydrocarbon by-product and diluent such ashydrofluorocarbon is recovered from a polymerization reaction processand sent to a polymer recovery system. Preferably, the polymer recoverysystem includes a purge system or vessel, more preferably a purge bin,and the polymer and associated entrained materials are sent to the purgesystem. The inert gas composition is then input into the purge system topurge or drive out the entrained materials, thereby forming a purgestream, which is recovered from the purge system.

Entrained, non-polymer product material that is separated and recoveredas a purge stream from the polymer product is preferably furtherseparated into component fractions or a plurality of streams and eachfraction or stream stored, recycled or removed as a waste stream fromthe system as appropriate. It is preferred that diluent and unreactedmonomer be separated and returned to the reactor. These streams can beseparated and recovered as individual streams or as a combined stream.If in inert gas is used in the recovery system, it is preferred that theinert gas also be separated, preferably as an individual stream, andrecovered for reuse in the polymer recovery system and/or in thereaction portion of the polymerization system.

Separation of the purge stream into a plurality of streams, and recoveryof those streams, can be accomplished by use of one or more separationsystems. In one embodiment, a mix of polymer, catalyst, unreactedmonomer, diluent and hydrocarbon by-product from the polymerizationreaction are purged with inert gas, and a polymer product stream and apurge gas stream are formed. From the purge gas stream a plurality ofstreams, including a hydrofluorcarbon containing stream, a nitrogencontaining stream and a waste stream are recovered using the one or moreseparation systems, preferably a condensation system and one or more ofa distillation system or barrier separation system.

A portion of the material that is entrained with the polymer effluentfrom the polymer reactor will be undesirable hydrocarbon by-productsthat should be vented from the system as a waste stream. Suchundesirable hydrocarbon by-products include ethane, butane, hexane,octane, and non-reactice internal olefins such as cis and trans2-hexene, 3-hexene, etc.

In one embodiment, the waste stream is vented by sending at least aportion of the waste stream to a flare system. In such an embodiment,the waste stream is low in non-combustible components as well as inmaterial that gives undesirable combustion products.

In one embodiment, the waste stream that is vented or flared is low indiluent material, particularly HFC diluent material. If the stream istoo high in diluents such as HFC, then flaring the material willproblems of environmental emissions (and potential corrosion in theflare system) due to the formation of HF, which can occur at theelevated temperatures associated with the combustion. These problems canbe effectively controlled by limiting rate of diluent material that isflared. Since the rate of the diluent will vary according to the rate offlow of total material to the reactor unit, one way to effectivelycontrol diluent vent rate is to limit the amount of diluent sent to thevent or flare system relative to the total rate of material that is sentto the polymerization reactor, which is defined herein as unitproduction flow rate (calculated on a weight to weight basis).Preferably, the waste stream, which contains HFC diluent material to beflared, is sent to the flare system at a hydrofluorocarbon flow rate tounit production flow rate of not greater than 0.1:1, preferably notgreater than 0.01:1, more preferably not greater than 0.001:1.

In another embodiment, the waste stream that is vented or flared is lowin content in inert gas that is used to scrub the polymer in the purgesystem. It is particularly desired to have a low concentration of inertgas that is non-combustible. Otherwise, purge gas that is sent to theflare system will adversely affect the flare system. In some cases,however, it will be effective to add a combustible gas to the purgestream in order to effect better burning of the stream. This isparticularly effective when the total volume of waste gas is low. Insuch case, only low volumes of combustible gas will need to be added.

In one embodiment, the waste stream is sent to the flare system with acontained flow rate of inert gas (nitrogen) that is not greater than 6%of unit production rate, on a weight to weight basis. Preferably, thecontained flow rate of inert gas is not greater than 3% of unitproduction rate, more preferably not greater than 1% of unit productionrate, and most preferably not greater than 0.5% unit production rate ona weight to weight basis.

One of the benefits of this invention is that the volumetric flow ofwaste material to vent or flare is substantially reduced overconventional systems. Since the volume of the waste stream that isflared is generally low, it is generally easier to maintain the desiredheat content of the waste stream that is to be flared. In oneembodiment, the heat content of the waste stream that is vented orflared stream is at least 300 BTU/scf (11,200 kJ/scm), preferably atleast 400 BTU/scf (14,900 kJ/scm). In cases where the heat content isless than desired, combustible hydrocarbon material is optionally addedto increase the BTU content prior to entering the flare system. Examplesof such combustible materials include natural gas, methane, and ethane.

In one embodiment, the waste stream that is to be vented or flared ispreferably high in combustible alkyl hydrocarbons. Examples of preferredcombustible alkyl hydrocarbons according to this invention include C₁ toC₈ alkyls, preferably one or more of methane, ethane, propane, linear orbranched butanes, linear or branched pentanes, linear or branchedhexanes, linear or branched heptanes, and linear or branched octanes. Itis preferred that the stream that is to be vented contain at total of atleast 5 wt % C₁ to C₈ alkyl hydrocarbons, preferably 5 to 15 wt %., andmore preferably at least 20 wt %.

Another benefit of the product recovery system of this invention is thatrecovery of inert streams such as nitrogen are provided. Such recoveredstreams can be reused to separate the non-polymer product from the fromthe polymer product in the purge system. In one embodiment, a nitrogenrich stream is separated and recovered. Preferably, the nitrogen streamis separated from the hydrocarbon by-products prior to flaring. Theseprated nitrogen stream preferably contains at least 50 mole %nitrogen, more preferably at least 60 mole % nitrogen, and mostpreferably at least 70 mole % nitrogen, based on total composition ofthe separated stream.

An example of how polymer and entrained material are separated andrecovered is shown in the polymer recovery system of FIG. 1 a. Accordingto the system shown in FIG. 1 a, polymer that contains entrained,unreacted monomer, HFC, as well as undesirable hydrocarbon by-productsfrom the polymerization reaction, is sent to a purge bin 100 through aline 102. Nitrogen purge gas is sent to the purge bin 100 through a line104 to scrub the polymer and remove the various entrained hydrocarbonmaterials.

The scrubbed polymer product is removed from the purge bin 100 through aline 105, and the purge gas and entrained hydrocarbon materials areremoved from the purge bin 100 through a line 106 as a purge stream. Thepurge stream is sent to a component separation system 108, where thecomponents are separated into a plurality of streams.

A nitrogen rich stream is removed from the separation system 108 througha line 110. The nitrogen rich stream can be recycled and sent to line104 or it can be used in any other desirable portion of the polymerreaction or recovery system.

The entrained monomer and HFC hydrocarbons are removed from theseparation system through one or more lines from the separation system108. In the embodiment shown in FIG. 1 a, the monomer and HFC areremoved in a single line, but these components can be further separatedas desired. It is preferred that the monomer and HFC be sent back to thepolymer reactor and that little to no monomer or HFC be vented orflared. Venting or flaring of HFC is particularly not desired in orderto minimize system corrosion or environmental emissions. It isparticularly desired to limit the amount of HFC going to the flaresystem as combustion of the HFC material will tend to form hydrofluoricacid and lead to corrosion as well as other environmental problems.

The material that is to be vented or flared is recovered by way of line114 as a waste stream. In the embodiment shown in FIG. 1, the wastestream is sent from line 114 to a flare system 116. When the combustiblehydrocarbon content or heat value of the waste stream going to the flaresystem 116 through line 114 is low, additional hydrocarbon (e.g.,natural gas) is added to the line 114 through a line 118.

The separation system 108 can include any type of separation devicecapable of separating the desired components in the purge stream that isrecovered from the treated polymer product. Examples of such devicesinclude those capable of performing the one or more of the followingprocesses: compression, flashing, cooling, condensation, distillation,absorption or adsorption.

In one embodiment the purge stream that is to be separated intocomponent streams is sent to a condenser. The condenser is operated atappropriate temperature and pressure conditions that condenses at least50 wt % of the hydrocarbon (including HFC) in the purge stream,preferably at least 60 wt %, more preferably at least 70 wt %.

In one embodiment, the purge stream is compressed to condense thehydrocarbon material. The condensed hydrocarbon material will typicallybe separated into at least two streams. One stream is generally alighter vapor stream and another condensed stream is generally a heavierliquid stream. The heavier condensed stream is preferably sent to thepolymer reactor, as it will contain significant quantities of monomerand/or diluent that would be desirable to reuse in the polymerizationprocess. At least a portion of the lighter condensed stream is vented orflared, as it will contain undesirable hydrocarbon compounds (such asethane) that are not to be returned to the polymer reactor.

In one embodiment, the condenser is operated at a pressure of from 15psig (103 kPa) to about 10,000 psig (69 MPa). Preferably, the condenseris operated at a pressure of from 20 psig (138 kPa) to about 1000 psig(7 MPa), more preferably from 25 psig (172 kPa) to about 500 psig (3kPa).

In another embodiment, the condenser is operated at a temperature offrom −60° C. to 30° C., preferably −20° C. to 10° C.

In one embodiment, a portion of the lighter condensed stream is ventedor flared. In a preferred embodiment, the lighter condensed stream isseparated into a hydrofluorocarbon containing stream, a waste stream,and an optional inert or nitrogen stream. Then the waste stream isflared.

The lighter condensed stream can be separated into the hydrofluorcarboncontaining stream, the waste stream and optional nitrogen stream by anymeans suitable for such separation. Preferred methods of separationinclude further compression, flashing and distillation, as well asvapor-liquid scrubbing and separation by selective barrier. Examples ofselective barriers include membrane separation and separation bypressure swing absorption.

Membranes suitable for use in this invention include selectivelypermeable membranes. Such membranes exhibit substantially differentpermeability for the various components that are desired to beseparated. In one embodiment, the membrane exhibits a substantiallydifferent permeability for the monomer material in the stream relativeto the HFC and/or inert purge gas or nitrogen. In another embodiment,the membrane exhibits a substantially different permeability for the HFCmaterial in the stream relative to the monomer and/or inert purge gas ornitrogen. In another embodiment, the membrane exhibits a substantiallydifferent permeability for the inert purge gas or nitrogen material inthe stream relative to the monomer and/or HFC.

In one embodiment, the membrane or membranes useful in this inventionare elastomeric membranes, which can be made from a variety of polymers.Examples of polymers that can be used to make elastomeric membranes,include, but are not limited to, nitrile rubber, neoprene,polydimethylsiloxane (silicone rubber), chlorosulfonated polyethylene,polysilicone-carbonate copolymers, fluoroelastomers, plasticizedpolyvinylchloride, polyurethane, cis-polybutadiene, cis-polyisoprene,poly(butene-1), polystyrene-butadiene copolymers,styrene/butadiene/styrene block copolymers, styrene/ethylene/butyleneblock copolymers, thermoplastic polyolefin elastomers, and blockcopolymers of polyethers, polyamides and polyesters.

In another embodiment, the membrane or membranes useful in thisinvention are glassy membranes, which can be made from a variety ofpolymers. Examples of polymers that can be used to make glassy membranesinclude, polysulfones, polyimides, polyamides, polyaramides,polyphenylene oxide, polycarbonates, ethylcellulose or celluloseacetate.

Super-glassy membranes can also be used in this invention. Super-glassypolymers have a rigid structure, high glass transition temperatures,typically above 100° C., 200° C. or higher, and would normally beexpected to be selective for smaller, less condensable molecules overlarger, more condensable molecules. However, membranes made from certainof these polymers that have unusually high free volume within thepolymer material have been found to exhibit anomalous behavior, in thatthey preferentially permeate larger, more condensable molecules oversmaller, less condensable molecules. One particular super-glassy polymeris poly(trimethylsilylpropyne), the use of which to preferentiallyseparate condensable components from lower-boiling, less condensablecomponents is described in U.S. Pat. No. 5,281,255, for example.

The membrane may be in the form of a homogeneous film, an integralasymmetric membrane, a multilayer composite membrane, a membraneincorporating a gel or liquid layer or particulates, or any other formknown in the art. In one embodiment, the membrane is a compositemembrane including a microporous support layer for mechanical strengthand a rubbery coating layer that is responsible for the separationproperties.

The membranes may be manufactured as flat sheets or as fibers and housedin any convenient module form, including spiral-wound modules,plate-and-frame modules and potted hollow-fiber modules. The making ofall these types of membranes and modules is well known in the art.Flat-sheet membranes in spiral-wound modules are our most preferredchoice.

In one embodiment, the membranes have a selectivity for thefaster-permeating component over the other components of at least about5, more preferably at least about 10 and most preferably at least about20, and a pressure-normalized flux of the faster-permeating component ofat least about 1×10⁻⁶ cm³ (STP)/cm²·sec·cmHg, more preferably at leastabout 1×10⁻⁵ cm³ (STP)/cm²·sec·cmHg.

The membrane separation system can be operated as a single membranesystem or a mult-membrane system. Typically, no driving force beyond acompressor in the condenser unit is needed to run the membrane unit.

In one embodiment, the membrane separation system is a single-stagemembrane separation operation using a membrane with a selectivity ofabout 20. Such a membrane system is capable of removing up to about 80or 90% of the preferentially permeating component from the feed streamand produce a permeate stream that has five times or more theconcentration of that component of the feed gas. Multistage or multistepprocesses, and variants thereof, can also be used. Such systems arefamiliar to those of skill in the art, may be configured in manypossible ways, including single-stage, multistage, multistep, or morecomplicated arrays of two or more units in series or cascadearrangements.

In one embodiment, the membrane separation step uses a membrane that isorganic-selective, that is, is selective for the monomer over thenitrogen purge gas and HFC. Preferably, such a membrane has a reasonablygood selectivity for the monomer over the purge gas and HFC, such asabout 10 or more. Removal of monomer from the membrane feed into thepermeate is reasonably high, such as about 50%, 80%, 90% or more.Generally, the membrane residue and permeate streams may typically be 5°C., 10° C. or more colder than the feed to the membrane unit, and it maybe both convenient and beneficial to use one or both cold streams fromthe membrane separation step to provide or supplement cooling for thecondensation step.

Pressure swing adsorption (PSA) processes provide an efficient andeconomical means for separating a multi-component gas stream containingat least two gases having different adsorption characteristics. The morestrongly adsorbed gas can be an impurity which is removed from the lessstrongly adsorbed gas which is taken off as product, or, the morestrongly adsorbed gas can be the desired product which is separated fromthe less strongly adsorbed gas.

In PSA processes, a multi component gas, such as the purge stream ofthis invention, is typically passed to at least one of a plurality ofadsorption zones at an elevated pressure effective to adsorb at leastone component, i.e. the more strongly adsorbed components, while atleast one other component passes through, i.e. the less stronglyadsorbed components. At a defined time, the passing of feedstream to theadsorber is terminated and the adsorption zone is depressurized by oneor more cocurrent depressurization steps wherein the pressure is reducedto a defined level which permits the separated, less strongly adsorbedcomponent or components remaining in the adsorption zone to be drawn offwithout significant concentration of the more strongly adsorbedcomponents. Then, the adsorption zone is depressurized by acountercurrent depressurization step wherein the pressure in theadsorption zone is further reduced by withdrawing desorbed gascountercurrently to the direction of the feedstream. Finally, theadsorption zone is purged and repressurized.

The more strongly adsorbed components are removed from the adsorber bedby countercurrently depressurizing the adsorber bed to a desorptionpressure. In general, lower desorption pressures are preferred in orderto provide more complete removal of the adsorbate during the desorptionstep. In addition, lower desorption pressures can provide a greatercapacity differential between adsorption and desorption conditions andthus increase the capacity of the process. In another embodiment of thisinvention rapid swing pressure adsorption is used to remove thefluorocarbon. Rapid pressure swing adsorption (RCPSA) is distinguishedfrom conventional pressure swing adsorption (PSA) by the shorter cycletime it employs. For example, RCPSA cycle times are typically less thana minute while conventional PSA cycle times are generally greater than 4minutes. With its shorter cycle time, RCPSA offers the advantages ofsmaller equipment size and lower cost. The principals of operation aresimilar for both methods, but the hardware (valving, piping,configuration of vessels, etc.) required to perform the cycles differsconsiderably between the two methods. While conventional PSA iscurrently in widespread use in refineries and chemical production plantsfor recovery and separation of gases such as hydrogen, RCPSA iscurrently in widespread use only for air separation. However,application of RCPSA for hydrogen purification in refineries hasrecently been disclosed in application (U.S. Ser. No. 60/645,713, filedJan. 21, 2005).

The invention can be carried out using virtually any adsorbent materialin the adsorber beds that has capacity for the adsorbate components.Suitable adsorbents known in the art and commercially available includecrystalline molecular sieves, activated carbons, activated clays, silicagels, activated aluminas and the like. The molecular sieves include, forexample, the various forms of silicoaluminophosphates andaluminophosphates disclosed in U.S. Pat. Nos. 4,440,871; 4,310,440 and4,567,027, hereby incorporated by reference as well as zeoliticmolecular sieves.

Zeolitic molecular sieves in the calcined form may be represented by thegeneral formula;Me₂O:Al₂O₃:xSiO₂:yH₂Owhere Me is a cation, x has a value from about 2 to infinity, n is thecation valence and y has a value of from about 2 to 10.

Typical well-known zeolites which may be used include, chabazite, alsoreferred to as Zeolite D, clinoptilolite, erionite, faujasite, alsoreferred to as Zeolite X and Zeolite Y, ferrierite, mordenite, ZeoliteA, and Zeolite P. Other zeolites suitable for use according to thepresent invention are those having a high silica content, i.e., thosehaving silica to alumina ratios greater than 10 and typically greaterthan 100. One such high silica zeolite is silicalite, as the term usedherein includes both the silicapolymorph disclosed in U.S. Pat. No.4,061,724 and also the F-silicate disclosed in U.S. Pat. No. 4,073,865,hereby incorporated by reference. Detailed descriptions of some of theabove-identified zeolites may be found in D. W. Breck, Zeolite MolecularSieves, John Wiley and Sons, New York, 1974, hereby incorporated byreference. The selection of a particular adsorbent for a particularseparation can be made by one skilled in the art with routineexperimentation and need not be further discussed herein.

It is often desirable when using crystalline molecular sieves that themolecular sieve be agglomerated with a binder in order to ensure thatthe adsorbent will have suitable physical properties. Although there area variety of synthetic and naturally occurring binder materialsavailable such as metal oxides, clays, silicas, aluminas,silica-aluminas, silica-zirconias, silica thorias, silica-berylias,silica-titanias, silica-aluminas-thorias, silica-alumina-zirconias,mixtures of these and the like, clay-type binders are preferred.Examples of clays which may be employed to agglomerate the molecularsieve without substantially altering the absorptive properties of thezeolite are attapulgite, kaolin, volclay, sepiolite, polygorskite,kaolinite, bentonite, montmorillonite, illite and chlorite. The choiceof a suitable binder and methods employed to agglomerate the molecularsieves are generally known to those skilled in the art and need not befurther described herein.

A PSA operation cycle useful in this invention includes the well knowncycle steps of adsorption, one or more equalization steps,countercurrent desorption, purge and repressurization. The cycle stepsare typically described with reference to their direction relative tothe adsorption step. Thus cycle steps wherein the gas flow is in aconcurrent direction to the adsorption step are known as “cocurrent”steps. Similarly cycle steps wherein the gas flow is countercurrent tothe adsorption step are known as “countercurrent” steps. During theadsorption step the feedstream is passed to the adsorber bed at anelevated adsorption pressure in order to cause the adsorption of theadsorbate and provide a product stream enriched in the first componentrelative to feedstream. During the equalization steps the pressure inthe depressurizing bed is released preferably cocurrently and theeffluent obtained therefrom, which is preferably rich in the firstcomponent, is passed in a countercurrent direction to another absorberundergoing repressurization. Typically at the conclusion of theequalization steps a provide purge step is initiated wherein theadsorber bed is further cocurrently depressurized to provide a purge gasthat is relatively impure with respect to the first component and thusis suitable for use as a purge gas. Optionally, instead of the providepurge step a portion of the product gas or gas obtained from one of theequalization steps can be used to supply the purge gas. Upon completionof the provide purge step, if employed, the adsorber bed iscountercurrently depressurized to a desorption pressure in order todesorb the adsorbate. Upon completion of the desorption step theadsorber bed is purged countercurrently with purge gas obtained fromanother adsorber bed. Finally the adsorber bed is repressurized, first,with equalization gas from other adsorber beds and then with feed orproduct gas to adsorption pressure. Other additional steps known tothose skilled in the art, such as for example, a copurge step whereinthe adsorber bed is cocurrently purged at an elevated pressure such asthe adsorption pressure with a purge stream comprising the adsorbate,can be employed.

Any flare apparatus or system capable of combusting the hydrocarboncomponents of the purge gas stream of this invention can be used tocombust the waste stream recovered according to this invention. Such asystem may include one or more flare stacks, and not only dispose of thewaste stream during normal operation but also can be utilized to disposeflammable waste gases or other flammable gas streams, which are divertedduring venting, shut-downs, upsets and/or emergencies.

Flaring of waste streams without producing smoke is preferred. In oneembodiment, the production of smoke is reduced by burning the wastestream in the presence of air and steam. In another embodiment, theproduction of smoke is reduced by burning the waste stream in thepresence of air only. In such an embodiment, the waste stream isintimately mixed with the air to fully oxide the hydrocarbon components.

In another embodiment, the hydrocarbon components of the waste streamare combusted with the use of regenerative thermal oxidizers (RTOs). Inan RTO unit, the waste stream is generally cycled through a firstchamber containing packing elements that have previously been heated andthen enters a combustion chamber where the combustible or pyrolyzablematerials in the waste stream are burned. The effluent is passed througha second chamber containing packing elements. These elements absorb atleast some of the heat from the effluent gases before they aredischarged to the atmosphere. When the elements have reached an elevatedtemperature such that heat transfer no longer occurs efficiently, theflow direction is reversed and the second chamber becomes the firstchamber and vice versa.

The packing elements in the chambers of an RTO can be in the form ofmonoliths with a plurality of through passages that are stacked withinthe chamber to provide a plurality of rectilinear parallel passagesthrough which the gas can flow on its way through the chamber.Alternatively, the elements are dumped in random fashion within thechamber so as to provide a large number of non-rectilinear routesthrough the chamber for the waste stream. The individual elements canhave a wide range of sizes and shapes such as hollow cylinders, with andwithout internal septa or other internal structures, cylinders withtriangular or “bow-tie” cross-sections, and porous pellets.

Waste streams that are particularly suitable for treatment using RTOsmay be generated for example when gas flows containing combustiblematerials that include a small quantity of halohydrocarbons. In suchapplications, it is preferred that the elements used in the RTO arecapable of absorbing heat rapidly and are stable under thermal cyclingconditions.

Typical packing elements for RTO applications are made fromclay/feldspathic material mixtures that have good stability to thermalcycling while having a good capacity to absorb heat. It is preferred thepacking elements are resistant to attack by the halogen-containingcomponents that may be in the waste stream. In a preferred embodiment,the packing elements include a ceramic packing element having an alkalimetal content that is not greater than 0.25% by weight, formed from afired mixture comprising 10 to 98%, and preferably from 35 to 65%, byweight of a clay having an alumina content of at least 36% by weight;from 2 to 90%, and preferably from 35 to 80%, by weight of a talccontaining at least 95% by weight of magnesium silicate as determined byX-ray diffraction analysis; and from 0 to 10%, preferably from 3 to 7%,of a dolomitic limestone containing at least 60 to 90% by weight ofcalcium carbonate and at least 10% and preferably 40 to 10%, by weightof magnesium carbonate and less than 10% of non-carbonate impurities.Such packing elements are described in greater detail in U.S. Pat. No.6,605,557, which is incorporated herein by reference.

A preferred embodiment of the invention is shown in FIG. 1 b. Theembodiment of FIG. 1 b is the same as that shown in FIG. 1 a, exceptthat polymer that contains the entrained hydrocarbon and HFC material isfirst sent to a flash tank 101. In the flash tank 101, the pressure isreduced causing the more volatile components to vaporize. The vaporizedcomponents are removed from the flash tank 101 by a line 103, and thepolymer and non-vaporized components are sent to the purge bin 100 byway of the line 102.

Another example of a polymer product recovery system of this inventionis shown in FIG. 2 a. This particular embodiment, incorporates the useof a first and second separation system to recover a plurality ofstreams that are either reused in the polymerization system or discardedas a waste stream to a flare system.

According to the embodiment shown in FIG. 2 a, polymer that containsunreacted monomer, HFC, as well as other entrained hydrocarbons,including undesirable hydrocarbon by-products from the polymerizationreaction, is sent to a purge bin 200 through a line 202. Nitrogen purgegas is sent to the purge bin 200 through a line 204 to scrub the polymerand remove the various entrained hydrocarbon materials.

The scrubbed polymer, also referred to as a degassed polymer product, isremoved from the purge bin 200 by way of a line 205. The purge stream,which contains the nitrogen purge gas and hydrocarbon materials scrubbedfrom the polymer are recovered from the purge bin 200 and sent through aline 206 to a first separation system 208. The separation system 208separates the purge stream into a hydrofluorocarbon containing streamand nitrogen containing stream. The hydrofluorocarbon containing stream,which contains a majority of the unreacted monomer and HFC sent to thepurge bin 200, is removed from the first separation system 208 by way ofa line 209. The nitrogen containing stream, which contains a majority ofthe nitrogen in the purge stream, is removed from the first separationsystem 208 by way of a line 210.

The nitrogen containing stream that is removed from the first separationsystem 208, is sent to through the line 210 to a second separationsystem 211. The second separation system 211 separates the nitrogenstream into a nitrogen rich stream and a waste stream. The nitrogen richstream, which contains a majority of the nitrogen from the nitrogenstream in the line 210, is recovered from the second separation system211 by way of a line 212.

The waste stream, which is also considered as a nitrogen lean stream, issent through a line 214 to a flare system 216. In cases where the wastegas is low in volume or heat content, additional hydrocarbon (e.g.,natural gas) is injected into the line 214 through a line 218.

An alternative embodiment of FIG. 2 a is shown in FIG. 2 b. Theembodiment in FIG. 2 b is the same as FIG. 2 a, except that the nitrogenrich stream is separated in the first reaction system 208 and removedthrough the line 209. In addition, the hydrocarbon rich stream,containing the majority of the unreacted monomer and HFC, is separatedin the second reaction system 211 and removed through the line 212.

A greater detail of one example of a polymer product recovery system ofthis invention is shown in FIG. 3. This particular embodiment,incorporates the use of a selective barrier system as part of theseparation system to separate components, and a flare system to combustunreuseable hydrocarbon separated from the polymer.

According to the embodiment shown in FIG. 3, polymer that containsunreacted monomer, HFC, and other hydrocarbons, including undesirablehydrocarbon by-products from the polymerization reaction, is sent to apurge bin 300 through a line 302. Nitrogen purge gas is sent to thepurge bin 300 through a line 304 to scrub the polymer and remove thevarious hydrocarbon material.

The scrubbed polymer, also referred to as a degassed polymer product, issent to a secondary purge tank 306, wherein additional nitrogen purgegas is injected through a line 308 to additionally scrub unreactedmonomer, HFC and other entrained hydrocarbon from the polymer. Polymerproduct is removed from the secondary purge tank 306 through a line 310.

Nitrogen purge gas, monomer, HFC and other entrained hydrocarbons areremoved from the purge bin 300 as a purge stream by way of a line 312,and the purge stream is sent to a separation system, which is comprisedof a condenser system 314 and a selective barrier system. The selectivebarrier system includes both a membrane system 316 and a pressure swingabsorption (PSA) system 318 in the particular embodiment shown in FIG.3.

In the embodiment shown in FIG. 3, the condenser system includes acompressor, settler drum and heat exchanger. The condenser system 314 isoperated as a conventional system in that the material sent to thesystem is compressed, cooled and separated into various componentsaccording to the respective boiling point ranges. In the FIG. 3,embodiment, a majority of the monomer and HFC are condensed andseparated as a liquid stream by way of a line 320. This liquid streamcan be further separated into component parts, for example bydistillation, or reused in the polymerization system, for example sentback to the reactor system.

Higher boiling point components are removed from the compressor systemby way of a line 322. The stream flowing through line 322 is a nitrogenrich line, and contains a majority of the nitrogen sent to the condensersystem 314.

The nitrogen rich stream in line 322 is sent to the membrane system 316to separate a nitrogen containing stream from the HFC, monomer, and/orother entrained hydrocarbon components. The membrane can be selectedaccording to the particular separation desired. In the embodiment shownin FIG. 3, a substantial portion of the monomer and/or HC components areseparated and sent through a line 324. If the stream flowing throughline 324 contains a substantial portion of hydrocarbon components notparticularly useful or desirable in the polymerization system, thecomponents are sent to a flare system 326 via line 327 as a wastestream. If the stream flowing through the line 324 contains asubstantial portion of useful monomer or other hydrocarbons useful inthe polymerization system, then the stream can be sent to a line 328back to the polymerization system.

The nitrogen containing stream leaving the membrane system 316 is passedthrough a line 330 to the PSA system 318, which, in the FIG. 3embodiment, is operated as a conventional two vessel, back-flush system.A stream high in nitrogen content exits the PSA system 318 and is senteither through a line 331 or 332. The high nitrogen content stream canbe vented to atmosphere through the line 332, but is preferably reusedin the polymerization or recovery system, such as by recycling thenitrogen through the line 331 to one or more of the lines 304 and 308.

The HFC rich stream separated in the PSA system 318 is recovered by wayof a line 334. The HFC stream is preferably reused in the polymerizationsystem, e.g., recycled to the polymerization reactor. If, however, theHFC stream becomes contaminated or degrades over time, a portion of thestream can be discarded in a manner appropriate to minimizeenvironmental contamination.

In another embodiment, activated carbon is used to remove thefluorocarbon(s) from the hydrocarbon streams and/or the waste streams.When using fluorocarbons in a process (such as a polymerization process)it is useful to prevent the escape of the fluorocarbons to theatmosphere. It is also useful to prevent the passage of fluorocarbons tothe flare or other combustion process. Specifically, in someembodiments, activated carbon is used to remove the fluorocarbons from agas or liquid process stream.

In another embodiment, the activated carbon would be used as theabsorbent material in a Pressure Swing Adsorption (PSA) process. A PSAprocess employs at least two separate adsorption columns. One columnoperates as the active column, adsorbing material from the flow streamwhile the other operates off-line (at reduced pressure) in the“regeneration” mode. When the adsorption capacity of the active columnis reached, the role of the columns is reversed. The alternating cyclesof this process provide an effectively continuous flow path through thesystem, and a continuous removal of certain components from the flowstream (i.e. those components that are strongly adsorbed by theactivated carbon, such as fluorocarbons). In another preferredembodiment, when using the activated carbon for removal of fluorocarbonsfrom a process stream, a PSA system of a given size could operated at areduced cycle frequency for improved reliability and reduced mechanicalwear on the switching valve components as compared to a process streamof hydrocarbons without fluorocarbons. In another preferred embodiment,a PSA system could be designed with smaller sized columns for reducedcost when using the activated carbon for removal of fluorocarbons from aprocess stream as compared to a process stream of hydrocarbons withoutfluorocarbon.

In an alternative embodiment, the activated carbon is used as a safety“guard bed” downstream of a primary separation system. The purpose ofthis guard bed would be to capture any fluorocarbon material that maybypass the primary separation system. In this case, the advantagesprovided by the activated carbon would be similar to that describedabove with PSA. The size (and cost) of the guard bed could be reducedsignificantly.

EXAMPLES

A series of absorption experimental runs were conducted in a simple,lab-scale column to determine the absorption capacity of two differenttypes of activated carbon obtained from a vendor. The absorptioncapacities were measured with both types of activated carbon using threedifferent types of hydrofluorocarbon (HFC-134a, HFC-236fa, andHFC-245fa). Results of these experiments are shown in Tables I and II.

The absorption column was a ½ inch (1.27 cm) OD stainless steel tubingwith valves fitted on either side. The ½ inch (1.27 cm) stainless steeltubing was 9⅞ inches long (25.1 cm) with an internal diameter of 0.430inch (10.9 mm). The column was packed with one of two types of activatedcarbon obtained from Calgon Carbon Corporation. The first sample wasdescribed by the vendor as “Calgon Activated Carbon, Type AP4-60.” Thesecond was described as “Calgon Activated Carbon, Type OVC Plus 4×6.”The AP4-60 activated carbon was in the form of cylindrically shapedpellets, while the OVC Plus material was in the form of flakes. Both ofthese carbons were crushed with a mortar and pestle to a smaller size tofit inside the absorption column. The crushing reduced the average sizeof the particles or flakes to approximately 25 to 50 percent of theiroriginal size, with some fines. Glass wool packing was inserted on bothends of the column (next to the valves) to prevent any carbon fromentering in to the valve areas. The HFC-245fa was obtained fromHoneywell, as marketed under their trade name Enovate 3000. TheHFC-236fa was obtained from DuPont, marketed as SUVA 236fa. The HFC-134awas an automotive grade material, marketed as R-134a. These materialswere used as received without purification.

The fluorocarbon was allowed to vaporize or boil from its holdingcontainer through a line that led to the bottom of the absorptioncolumn. Between the column and the HFC source were two rotameters (flowindicating devices). Each rotameter had a flow range of 50 ml/min of airat 21.1° C. at atmospheric pressure. The rotameters were arranged inparallel to provide a flow range of 100 ml/min of air at atmosphericpressure. (The actual flow range of the rotameter depends on the Mw ofthe gas. For a gas of known Mw, the actual flow rate can be obtainedfrom the indicated flow rate using methods that are well known in theart.) On the exit side of the absorption column, a ¼ inch (0.64 cm) linewas directed down to a coil of stainless steel tubing that was containedwithin a beaker of dry ice. The chilled coil of stainless steel tubingacted as a condenser to liquefy (and detect) fluorocarbon gas comingfrom the absorption column. The downstream end of the condenser coil wasvented to the atmosphere within a fume hood. Prior to each run, theweight of the empty column (with glass wool and valves) was weighed andrecorded as the tare weight. The column was weighed again after theaddition of activated carbon. The column was then connected to the feedand exit lines, and fluorocarbon (as a gas) was passed through theadsorption column. The flow rate of fluorocarbon was set at an indicated25 to 30 ml/min on each rotameter. Initially there was no fluorocarboncondensed in the coil, indicating that the fluorocarbon was beingadsorbed by the activated carbon in the column. Flow through the columnwas continued until some liquid began to “spit” out of the end of thecondenser. This indicated that fluorocarbon was no longer being adsorbedby the column, and the limiting adsorption capacity had been reached.The flow of fluorocarbon gas was allowed to continue one more minute toensure complete saturation, and the flow was then stopped. The valves oneither side of the absorption column were closed and then the columnremoved and weighed. The increase in weight of the absorption column wastaken as the weight of fluorocarbon adsorbed. Upon the completion of therun, the valves were removed and the activated carbon was poured out toprepare for the next test. No gas release was observed when opening orremoving the valves, indicating that the fluorocarbon initially adsorbedduring the tests remained adsorbed on the activated carbon. TABLE IActivated Carbon Absorption Results With Fluorocarbon (FC) Wt. Empty Wt.of Tube Activated FC Mw Tube, w/ valves w/ Carbon Carbon Type FC Type(g/mole) (g) (g) AP4-60 HFC-245fa 134 394.30 406.42 AP4-60 R-134a 102394.45 406.74 AP4-60 HFC-236fa 152 394.41 407.14 OVC Plus HFC-236fa 152394.46 405.10 OVC Plus R-134a 102 394.44 405.68 OVC Plus HFC-245fa 134394.45 405.65

TABLE II Wt. of Tube FC/C Wt. w/ Carbon Wt. of FC Ratio Activated Carbon& FC Absorbed by FC/C Molar Carbon Type (g) (g) (g) Weight Ratio AP4-6012.12 412.75 6.33 0.522 0.0468 AP4-60 12.29 410.93 4.19 0.341 0.0401AP4-60 12.73 413.81 6.67 0.524 0.0414 OVC Plus 10.64 411.39 6.29 0.5910.0467 OVC Plus 11.24 410.92 5.24 0.466 0.0549 OVC Plus 11.20 412.396.74 0.602 0.0539The above tests indicate that the activated carbon materials hadsurprisingly high adsorption capacities of between 34 to 60 percent offluorocarbons by weight as indicated in Tables I and II. Thus in apreferred embodiment, the vent streams from a process could be purified(i.e. fluorocarbon removed) with reduced amounts of activated carbonthan would normally be used in an activated carbon bed in a hydrocarbonprocess.

Having now fully described this invention, it will be appreciated bythose skilled in the art that the invention can be performed within awide range of parameters within what is claimed, without departing fromthe spirit and scope of the invention. All documents described hereinare incorporated by reference herein, including any priority documentsand/or testing procedures. Likewise, the term “comprising” is consideredsynonymous with the term “including” for purposes of Australian law.

1. A process for polymerizing one or more hydrocarbon monomer(s) in areactor system, the reactor system comprising a reactor and a flaresystem, the process comprising the steps of: a) mixing together acatalyst system, the one or more monomers and a hydrofluorocarbon in thereactor to produce polymer; b) recovering from the mixture a pluralityof streams, including a hydrofluorocarbon containing stream, a polymerproduct stream and a waste stream; and c) sending at least a portion ofthe waste stream to the flare system.
 2. The process of claim 1, whereinthe waste stream is sent to the flare system at a hydrofluorocarbon flowrate to unit production flow rate of not greater than 0.1:1.
 3. Theprocess of claim 2, wherein the waste stream is sent to the flare systemat a hydrofluorocarbon flow rate to unit production flow rate of notgreater than 0.01:1
 4. The process of claim 3, wherein the waste streamis sent to the flare system at a hydrofluorocarbon flow rate to unitproduction flow rate of not greater than 0.001:1.
 5. The process ofclaim 1, wherein the mixture is purged with a nitrogen stream and thenthe plurality of streams is recovered.
 6. The process of claim 5,wherein the plurality of recovered streams includes a nitrogencontaining stream.
 7. The process of claim 6, wherein the nitrogencontaining stream contains a majority of the nitrogen used to purge thepolymer product.
 8. The process of claim 5, wherein the waste streamcontains nitrogen and is sent to the flare system at a nitrogen flowrate that is not greater than 6% of unit production rate.
 9. The processof claim 8, wherein the waste stream is sent to the flare system at anitrogen flow rate that is not greater than 3% of unit production rate.10. The process of claim 9, wherein the waste stream is sent to theflare system at a nitrogen flow rate that is not greater than 1% of unitproduction rate.
 11. The process of claim 10, wherein the waste streamis sent to the flare system at a nitrogen flow rate that is not greaterthan 0.5% unit production rate.
 12. The process of claim 1, wherein theplurality of streams is recovered through one or more separation systemscomprising compression, flashing, cooling, condensation, distillation,selective barrier separation or a combination thereof.
 13. The processof claim 12, wherein the plurality of streams is recovered throughcondensation and selective barrier separation.
 14. The process of claim1, wherein the polymerization process is a solution process, gas phaseprocess, slurry phase process, medium pressure process, high pressureprocess or a combination thereof.
 15. A polymerization process,comprising the steps of: a) forming a polymer in the presence of ahydrofluorocarbon; b) recovering a majority of the polymer in a polymerproduct stream and a majority of the hydrofluorocarbon in a purgestream; c) separating the purge stream into a plurality of streamsincluding a hydrofluorocarbon containing stream and a waste stream; andd) sending at least a portion of the waste stream to a flare stream. 16.The process of claim 15, wherein the recovered polymer product streamcontains not greater than 100 wppm total hydrofluorocarbon, based ontotal weight of the recovered polymer product stream.
 17. The process ofclaim 15, wherein the waste stream contains hydrofluorocarbon and issent to the flare system at a hydrofluorocarbon flow rate to unitproduction flow rate of not greater than 0.1:1.
 18. The process of claim17, wherein the waste stream is sent to the flare system at ahydrofluorocarbon flow rate to unit production flow rate of not greaterthan 0.01:1
 19. The process of claim 18, wherein the waste stream issent to the flare system at a hydrofluorocarbon flow rate to unitproduction flow rate of not greater than 0.001:1.
 20. The process ofclaim 15, wherein the majority of the hydrofluorocarbon is recovered inthe purge stream by purging the polymer with nitrogen.
 21. The processof claim 20, wherein a nitrogen stream is recovered from the purgestream.
 22. The process of claim 21, wherein the waste stream containsnitrogen and is sent to the flare system at a nitrogen flow rate that isnot greater than 6% of unit production rate.
 23. The process of claim22, wherein the waste stream is sent to the flare system at a nitrogenflow rate that is not greater than 3% of unit production rate.
 24. Theprocess of claim 23, wherein the waste stream is sent to the flaresystem at a nitrogen flow rate that is not greater than 1% of unitproduction rate.
 25. The process of claim 24, wherein the waste streamis sent to the flare system at a nitrogen flow rate that is not greaterthan 0.5% unit production rate.
 26. The process of claim 21, wherein therecovered nitrogen stream is used to purge the polymer ofhydrofluorocarbon.
 27. The process of claim 15, wherein the purge streamis separated into a plurality of streams through one or more separationsystems comprising compression, flashing, cooling, condensation,distillation, selective barrier separation or a combination thereof. 28.The process of claim 27, wherein the purge stream is separated into aplurality of streams through condensation and selective barrierseparation.
 29. The process of claim 15, wherein the polymerizationprocess is a solution process, gas phase process, slurry phase process,medium pressure process, high pressure process or a combination thereof.30. A polymer recovery process, comprising the steps of: a) separatinghydrofluorocarbon from a polymer; b) recovering the separatedhydrofluorocarbon in a purge stream and the polymer in a polymer productstream; c) separating the purge stream into a plurality of streamsincluding a hydrofluorocarbon containing stream and a waste stream; andd) sending at least a portion of the waste stream to a flare system. 31.The process of claim 30, wherein the recovered polymer product streamcontains not greater than 100 wppm total hydrofluorocarbon, based ontotal weight of the recovered polymer product stream.
 32. The process ofclaim 30, wherein the waste stream contains hydrofluorocarbon and issent to the flare system at a hydrofluorocarbon flow rate to unitproduction flow rate of not greater than 0.1:1.
 33. The process of claim32, wherein the waste stream is sent to the flare system at ahydrofluorocarbon flow rate to unit production flow rate of not greaterthan 0.01:1
 34. The process of claim 33, wherein the waste stream issent to the flare system at a hydrofluorocarbon flow rate to unitproduction flow rate of not greater than 0.001:1.
 35. The process ofclaim 30, wherein the hydrofluorocarbon is recovered in the purge streamby purging the polymer with a nitrogen stream.
 36. The process of claim30, wherein the plurality of streams includes a nitrogen containingstream.
 37. The process of claim 36, wherein the waste stream containsnitrogen and is sent to the flare system at a nitrogen flow rate that isnot greater than 6% of unit production rate
 38. The process of claim 37,wherein the waste stream is sent to the flare system at a nitrogen flowrate that is not greater than 3% of unit production rate.
 39. Theprocess of claim 38, wherein the waste stream is sent to the flaresystem at a nitrogen flow rate that is not greater than 1% of unitproduction rate.
 40. The process of claim 39, wherein the waste streamis sent to the flare system at a nitrogen flow rate that is not greaterthan 0.5% unit production rate.
 41. The process of claim 35, wherein thenitrogen containing stream is used to separate hydrofluorocarbon fromthe polymer.
 42. The process of claim 30, wherein the purge stream isseparated into the plurality of streams through one or more separationsystems comprising compression, flashing, cooling, condensation,distillation, selective barrier separation or a combination thereof. 43.The process of claim 42, wherein the purge stream is separated into theplurality of streams through condensation and selective barrierseparation.
 44. A polymerization process, comprising the steps of: a)polymerizing at least one monomer to form polymer in a mixturecontaining hydrofluorocarbon; b) recovering from the mixture a pluralityof streams, including a waste stream; and c) sending at least a portionof the waste stream to a flare system.
 45. The process of claim 44,wherein the waste stream contains hydrofluorocarbon and is sent to theflare system at a hydrofluorocarbon flow rate to unit production flowrate of not greater than 0.1:1.
 46. The process of claim 45, wherein thewaste stream is sent to the flare system at a hydrofluorocarbon flowrate to unit production flow rate of not greater than 0.01:1.
 47. Theprocess of claim 46, wherein the waste stream is sent to the flaresystem at a hydrofluorocarbon flow rate to unit production flow rate ofnot greater than 0.001:1.
 48. The process of claim 44, wherein the wastestream contains nitrogen and is sent to the flare system at a nitrogenflow rate that is not greater than 6% of unit production rate
 49. Theprocess of claim 48, wherein the waste stream is sent to the flaresystem at a nitrogen flow rate that is not greater than 3% of unitproduction rate.
 50. The process of claim 49, wherein the waste streamis sent to the flare system at a nitrogen flow rate that is not greaterthan 1% of unit production rate.
 51. The process of claim 50, whereinthe waste stream is sent to the flare system at a nitrogen flow ratethat is not greater than 0.5% unit production rate.
 52. The process ofclaim 44, wherein the polymerization is a solution process, gas phaseprocess, slurry phase process, medium pressure process, high pressureprocess or a combination thereof.
 53. The process of claim 44, whereinthe plurality of streams is recovered by purging the mixture with anitrogen stream.
 54. The process of claim 53, wherein the plurality ofstreams includes a hydrofluorocarbon containing stream and a nitrogencontaining stream.
 55. The process of claim 54, wherein thehydrofluorocarbon containing stream contains a majority of thehydrofluorocarbon contained in the mixture.
 56. The process of claim 54,wherein the nitrogen containing stream contains a majority of thenitrogen used to purge the mixture.
 57. The process of claim 1, whereinthe waste stream is passed through activated carbon prior to being sentto the flare.
 58. The process of claim 15, wherein the waste stream ispassed through activated carbon prior to being sent to the flare. 59.The process of claim 30, wherein the waste stream is passed throughactivated carbon prior to being sent to the flare.
 60. The process ofclaim 44, wherein the waste stream is passed through activated carbonprior to being sent to the flare.